Interactions between the science teaching orientations and components of pedagogical content knowledge of in-service chemistry teachers

Betul Ekiz-Kiran *a and Yezdan Boz b
aVan Yuzuncu Yil University, College of Education, Dept. of Maths. & Sci. Edu., Van, Turkey. E-mail: betulekiz@gmail.com
bMiddle East Technical University, College of Education, Dept. of Maths. & Sci. Edu., Ankara, Turkey

Received 29th March 2019 , Accepted 6th July 2019

First published on 20th August 2019


The purpose of this study was to examine the interactions between in-service chemistry teachers’ science teaching orientations and other components of their pedagogical content knowledge (PCK). Two experienced chemistry teachers participated in this study. Data were collected through interviews, classroom observations, and field notes as the participants taught the mixtures unit. The results indicated that the participants held solid foundation purposes, in which students use science to be successful in their exams or next classes, along with everyday coping and correct explanations purposes. When participants’ correct explanations and solid foundation purposes interacted together with the same PCK component, solid foundation appeared to be the reason for their correct explanations purpose. The teaching strategies that teachers preferred to use interacted with their solid foundation and correct explanations purposes, and the participants altered curricula only if they believed it would lead students to achieve better scores on examinations. Participants’ beliefs about science teaching and learning indicated aspects of teacher-focused beliefs that prevent teachers from focusing on students’ prerequisite knowledge, learning difficulties, and misconceptions. These beliefs interacted with all the sub-components of knowledge of instructional strategies. In addition, there was an interaction between knowledge of curricula and beliefs about science teaching and learning for participants that were more knowledgeable about the curriculum. Moreover, what the teachers assessed was related to their correct explanations and everyday coping beliefs, while the way they assessed was related to their solid foundation beliefs. Last, none of the participants emphasised the aspects of the nature of science during their instruction.


Introduction

In recent years, there has been a shift from traditional teacher-focused science instruction to activity-based, student-centred classes enriched with activities that incorporate reform-based science teaching and learning practices. Reform-based practices are consistent with the nature of science (NOS) inquiry and reflect the values of scientific knowledge (American Association for the Advancement of Science [AAAS], 1993). In order to meet the requirements of the reforms, teacher education programs aim to provide science teachers with an understanding of the merits of reform-based teaching and learning practices and to prepare teachers to employ them in their classes (AAAS, 1993; National Research Council, 1996). It is necessary to change in-service teachers’ traditional views on teaching and learning to support their ability to keep pace with these reforms (Friedrichsen, 2002). To adapt to these changes, teachers’ beliefs about science teaching and learning should be considered because the use of reform-based practices is affected by teachers’ beliefs (Friedrichsen, 2002; Jones and Carter, 2007; Fletcher and Luft, 2011). Teachers’ behaviours and decisions and thus the ways in which they teach are highly influenced by personal beliefs (Pajares, 1992). For instance, while teachers with traditional beliefs tend to employ teacher-focused instruction and do not allow students to actively participate, teachers with constructivist beliefs are likely to employ student-centred instruction to help students construct their own understanding (Tsai, 2002). Accordingly, it is essential to take teachers’ beliefs into consideration to be informed about their teaching practices.

Teachers’ knowledge is also an undeniable component of teaching. It is obvious that teachers should have adequate subject matter knowledge in order to teach. However, the possession of subject matter knowledge alone does not make teachers successful; teachers must also know how to teach the related subject matter (Shulman, 1986). In support of this view, Tamir (1988) stated that being capable of teaching subject matter is as important as having adequate subject matter knowledge.

Pedagogical content knowledge (PCK) refers to the combination of teachers’ beliefs and knowledge (Magnusson et al., 1999). Magnusson et al. (1999) proposed five components of PCK: science teaching orientations (STO), knowledge of learners (KofL), knowledge of curricula (KofC), knowledge of instructional strategies (KofIS), and knowledge of assessment (KofA). In these components, STO are mostly related to teacher beliefs and influence teacher practice by shaping the other components of PCK (Magnusson et al., 1999; Friedrichsen et al., 2011). According to Abell (2008), research on the interactions between STO and the other components of PCK plays a significant role in determining the quality of teachers’ PCK. Following Abell's recommendations, researchers have consistently found that a greater number of interactions between the components is a criterion for a well-developed and complex, and hence, more qualified PCK (e.g.Park and Chen, 2012; Aydin and Boz, 2013; Aydin et al., 2015). Correspondingly, the purpose of this study is to examine how in-service chemistry teachers’ STO and other components of PCK interact.

Theoretical framework

Pedagogical content knowledge

PCK was first suggested by Shulman (1986) as a kind of content knowledge that “goes beyond knowledge of subject matter per se to the dimension of subject matter knowledge for teaching” (p. 9). Later on, Shulman (1987) defined PCK as a “special amalgam of content and pedagogy that is uniquely the province of teachers, their own special form of professional understanding” (p. 8). The concept has been developed over time and researchers have proposed various designs for PCK (Grossman, 1990; Marks, 1990; Cochran et al., 1993; Magnusson et al., 1999). Research in science education has widely used the PCK model defined by Magnusson et al. (1999). This model is based on a specialized teacher knowledge that is used to transform content knowledge into knowledge for teaching subject matter (Shulman, 1987; Magnusson et al., 1999). The first component of the model, KofL, refers to teacher knowledge about students and includes two categories, which are the requirements for learning specific science concepts (i.e., students’ prerequisite knowledge) and areas of science that students find difficult (i.e., students’ difficulties and misconceptions about a topic). KofC includes knowledge of goals and objectives, and specific programs and materials stated in the curriculum. KofIS includes subject and topic-specific instructional strategies that a teacher must use to instruct students in a specific topic. The last component, KofA, consists of two categories: knowledge of the dimensions of science learning to assess and methods of assessing science learning. Aydin et al. (2014) modified Magnusson et al.'s PCK model by adding vertical–horizontal relations and altering the curriculum dimensions to KofC and the purpose of assessment to KofA. In this study, the modified version of Magnusson et al.'s model was used for the KofL, KofC, KofIS, and KofA components as it allows for a wider perspective.

Science teaching orientations

Throughout the history of research on PCK, scholars have used various terms to refer to STO. Shulman's original model of PCK did not include STO as a component. Grossman (1990) proposed the component conceptions of purposes for teaching subject matter for the first time; this component “includes knowledge and beliefs about the purposes for teaching a subject at different grade levels. These overarching conceptions of teaching a subject are reflected in teachers’ goals for teaching particular subject matter” (Grossman, 1990, p. 8). Later, Magnusson et al. (1999) suggested that “an orientation represents a general way of viewing or conceptualizing science teaching” (p. 97) and teachers’ orientations manage many of their instructional decisions. Their STO conceptualisation consists of nine categories: activity-driven, didactic, discovery, conceptual change, process, academic rigor, inquiry, project-based science, and guided-inquiry. While the first four orientations were the same as the orientations proposed by Anderson and Smith (1987), the rest originated from different sources in the literature (e.g. guided inquiry originated from Magnusson and Palinesar, 1995). Outside of Grossman and Magnusson et al.'s perspective, Anderson and Smith (1987) defined teachers’ STO and learning as “general patterns of thought and behaviour related to science teaching and learning” (p. 99). They described four general patterns: activity-driven teaching, didactic teaching, discovery teaching, and conceptual change teaching regarding teachers’ orientations to science teaching and learning.

Magnusson et al.'s categorisation of STO has been used in a number of studies (e.g.Volkmann et al., 2005; Park and Oliver, 2008; Aydin et al., 2015). However, Friedrichsen et al. (2011) criticised this categorisation in their position paper; they claimed that assigning a teacher to the most dominant orientation of the nine is problematic. They also examined other studies on STO and suggested three more issues related to the use of STO. The first issue is that researchers use orientations in different and unclear ways in their studies due to the lack of a single definition of STO. The second issue is that there is an unclear or absent relationship between orientations and the other components of the model. Even though orientations were described as shaping the other components of PCK (Magnusson et al., 1999), researchers have neither investigated the relationship between the orientations and the other PCK components nor have they given detailed explanations of how orientations shape them. The last issue is ignoring orientation even if it is labelled as the overarching component (Grossman, 1990). Considering these issues, to clarify the STO construct, Friedrichsen et al. (2011) defined STO as an interrelated set of beliefs consisting of beliefs about the purposes of science teaching, beliefs about science teaching and learning, and beliefs about the NOS.

The current study utilises Friedrichsen et al.'s conceptualisation of STO. The PCK model used in this study is a combination of Friedrichsen et al.'s (2011) conceptualisation of STO and Magnusson et al.'s (1999) modified version of the PCK model. The components and sub-components of the PCK model used in this study are given in Table 1.

Table 1 PCK model used in this study
Components of PCK Sub-components of PCK
Science teaching orientations Beliefs about the purposes of science teaching
Beliefs about science teaching and learning
Beliefs about the nature of science
 
Knowledge of learners Prerequisite knowledge
Misconceptions
Difficulties
 
Knowledge of curricula Knowledge of goals and objectives
Relating to other topics (vertical–horizontal)
Relating to other disciplines
Altering the curriculum
 
Knowledge of instructional strategies Subject specific strategies
Topic specific activities
Topic specific representations
 
Knowledge of assessment Methods of assessment (the way of assessment)
Dimensions of science learning to assess
(what is assessed – purpose of assessment)


Research on science teaching orientations

Research on STO conducted with in-service teachers has utilised Anderson and Smith's (1987) STO definition (e.g.Nargund-Joshi et al., 2011), the central and peripheral goals of teachers (e.g.Friedrichsen and Dana, 2005), Friedrichsen et al.'s (2011) STO conceptualisation (e.g.Campbell et al., 2013; Boesdorfer and Lorsbach, 2014), or PCK-based NOS instruction (e.g.Faikhamta, 2013). For instance, Nargund-Joshi et al. (2011) used Anderson and Smith's (1987) STO definition in their study in which they aimed to elicit Indian teachers’ STO and explore whether their orientations were consistent with their practices. One salient result of the study was that participant teachers aimed to assess students’ understanding to prepare their students for board exams. As these exams play an important role in the Indian educational system, teachers want their students to achieve high scores. In another study, Friedrichsen and Dana (2005) proposed that assigning teachers to one orientation may not reflect teachers’ actual orientations. Instead, they preferred to use central and peripheral goals to describe teachers’ orientations. In this description, while central goals refer to the dominant orientation, peripheral goals refer to goals that have less influence on teachers’ instructional practices. Moreover, Boesdorfer and Lorsbach (2014) used Friedrichsen et al.'s (2011) refined the definition of STO, although they did not include beliefs about the NOS in their study. In Campbell et al.'s (2013) study on beliefs about the NOS, none of the orientations profiles showed complex beliefs. In the context of PCK-based NOS instruction, Faikhamta (2013) aimed to enhance science teachers’ understandings and teaching of NOS. The results of the study revealed that at the beginning of the instruction participants had naive ideas regarding the NOS and their goals for NOS instruction aligned with project-based science and science process skills. However, at the end of the instruction, participants enhanced their understanding of the NOS and their orientations to teaching the NOS.

Interaction studies involving science teaching orientations

Interactions among the components of PCK have attracted researchers’ attention in recent years. However, there are few studies investigating the interactions between STO and the other PCK components in the literature. Even in the few studies on this topic, interactions with STO have not been examined in depth. This underestimation has led to the prominence of research on the interactions among the other four components.

Numerous studies have been conducted with pre-service teachers utilising Magnusson et al.'s (1999) nine categories of STO (e.g.Aydin et al., 2015) or Friedrichsen et al.'s (2011) conceptualisation of STO (e.g.Demirdöğen, 2016). Aydin et al.'s (2015) study found that while all participants had didactic central goals, their peripheral goals included dual combinations of process, activity-driven, conceptual change, and academic rigor orientations. In Demirdöğen's (2016) study, results were given in three assertions, the first of which was that pre-service teachers’ purpose of science teaching informs the PCK component it interacts with. Second, pre-service teachers’ beliefs about the NOS interacted with their PCK only if they were directly related to their purposes of science teaching. Third, beliefs about science teaching and learning generally interacted with KofIS.

Studies with in-service teachers (e.g.Park and Chen, 2012; Aydin and Boz, 2013) revealed that the integration among the PCK components was idiosyncratic and topic-specific. Moreover, Park and Chen (2012) proposed that didactic STO directed KofIS by inhibiting its connections with the other components of PCK. Likewise, Aydin and Boz (2013) suggested that STO shaped the instructional decisions of teachers, behaving as the overarching component of PCK.

Significance of this study

The complex and stable nature of beliefs may act like a filter that influences teachers’ instructional decisions (Luft and Roehrig, 2007). STO are a central component of PCK, as they direct the way teachers teach (Kind, 2016). Therefore, unveiling teachers’ STO and how they affect teachers’ classroom practices are worth investigating to prepare highly-qualified teachers. For this purpose, teachers’ beliefs should be made visible (Luft and Roehrig, 2007).

According to the claims of Magnusson et al. (1999), STO can be considered as the overarching component of PCK. Even though STO play a major role among the other components of PCK, in most of the PCK studies they are ignored and have not been empirically investigated (Friedrichsen et al., 2011). Abell (2008) proposed that “PCK is more than the sum of these constituent parts” (p. 1407); thus, all the components of PCK should be studied together to present the whole picture. While the KofL and KofIS components take the lead in PCK studies, the STO component is often neglected. Although it is defined as the central component of PCK that influences and is influenced by the other components, the relationships between STO and the other components of PCK are either unclear or absent in the PCK literature (Abell, 2008; Friedrichsen et al., 2011).

Science teaching orientations are an important indicator of teachers’ classroom practice (Grossman, 1990; Gess-Newsome, 2015) and have an effect on how teachers act in their classrooms (Kind, 2016). Instructional decisions such as planning a lesson, choosing a teaching approach, determining the assessment method, and decisions about the course objectives are influenced by teachers’ STO (Borko and Putnam, 1996). Knowing more about PCK components and their interactions helps researchers to identify methods for developing more qualified teachers (Kind, 2016).

Research on STO has been mostly carried out for prospective teachers, and few empirical studies have been conducted with secondary teachers. More studies conducted with in-service teachers are needed to clarify and understand more about their STO (Friedrichsen and Dana, 2005; Abell, 2008; Friedrichsen et al., 2011). Studies investigating the interactions between in-service teachers’ STO and the other components of PCK are needed, as most interaction studies were conducted with prospective teachers (Friedrichsen et al., 2011; Demirdöğen, 2016). It is important to identify the PCK of in-service teachers to understand the training of prospective and beginning teachers (Abell, 2008; Henze et al., 2008; Kind, 2009; Schneidler and Plasman, 2011).

Another notable point about PCK research is that it should be studied in the context of classroom settings to capture the complex interactions among the components of PCK (Baxter and Lederman, 1999; Friedrichsen and Dana, 2005; Gess-Newsome, 2015). Abell (2008) called for research in classrooms to examine the value that classroom observations add to PCK research.

This study aims to investigate in-service chemistry teachers’ PCK components – STO, KofL, KofC, KofIS and KofA – to examine the interactions between STO and the other components of PCK in the mixtures unit. The research question that guides this study is:

How do the STO of experienced in-service chemistry teachers interact with the other components of pedagogical content knowledge?

Methodology

The current study is qualitative in nature. In qualitative research, by spending time in the actual research setting, the researcher is “concerned with understanding behaviour from the informant's own frame of reference” (Bogdan and Biklen, 2007, p. 2). In this study, the informants were two in-service chemistry teachers and the settings were their classrooms.

Participants

Two experienced chemistry teachers working at public high schools participated in the study. Mete (male) and Ece (female) both received BS degrees in chemistry education and had 32 and 27 years of teaching experience, respectively.

Context of this study

The current study was conducted in a school context in which nation-wide examinations were given great importance. To be admitted to a highly regarded high school, students must receive high scores on exams conducted at the end of middle school. After four years of high school, students must take the Higher Education Examination (HEE) and Undergraduate Placement Examination (UPE) to be admitted to a program at the university level. Mete and Ece both worked at high schools of the same level that accepted students with high middle school exam scores. The participant teachers’ schools were two of the top five schools in the city.

Chemistry topic of this study

During this study, Mete and Ece were teaching the mixtures unit in the 10th grade chemistry curriculum. The time allocated for this unit was 16 class hours. The mixtures unit included three main topics: homogeneous mixtures, heterogeneous mixtures, and the separation of mixtures. The sub-topics of the unit were dissolution, concentration of solutions, colligative properties, types of heterogeneous mixtures, and methods for separating mixtures. Some of the chemistry concepts students were expected to learn in this unit were suspension, emulsion, dissolution, solvent, solute, concentration, ppm, osmotic pressure, colligative properties, filtering, distillation, and dialysis. Examples of learning objectives for this unit were “Students can explain dissolution by using intermolecular interactions” and “Students can interpret the properties of solutions related to daily life.”

Data collection sources

Interviews, observations, field notes, and classroom documents were used to collect data. The timeline of data collection is provided in Table 2.
Table 2 Timeline of this study
1. Meeting Meeting with the teacher
Explanation of the study
 
2. Meeting (interviews) Background information
Beliefs about the goals or purposes of science teaching
Beliefs about science teaching and learning
 
3. Meeting (interviews) VNOS
The other PCK components (KofL, KofC, KofIS, KofA)
 
4. Meeting (interviews) Mixtures unit
 
Instruction Participant observation for 8 weeks – 16 class hours
 
Weekly interviews Interviews after each instruction


Interviews. During data collection, five different types of interviews were conducted with the participants (see Table 2) concerning the teachers’ background information, STO, other PCK components, their knowledge about the mixtures unit, and their reflections on each instruction. All interviews were recorded using a digital audio recorder.

Interviews about teachers’ background information were conducted to obtain detailed information about teachers’ education levels, teaching and learning experiences, and views about being a teacher. The purpose of the interviews conducted at the second meeting was to elicit and elaborate on teachers’ beliefs about the purposes of teaching chemistry and their beliefs about science teaching and learning. Interview questions were constructed based on the suggestions of the available literature (Friedrichsen, 2002; Luft and Roehrig, 2007; Friedrichsen et al., 2009; Friedrichsen et al., 2011; Boesdorfer, 2012). The last interview on STO was about teachers’ beliefs regarding the NOS. Views of the NOS Questionnaire Form C (VNOS-C) developed by Lederman et al. (2002) were used to determine teachers’ beliefs about the NOS.

The purpose of the interview about the other PCK components (KofL, KofC, KofIS, and KofA) was to determine how the participants used these components throughout their instruction. Interview questions were prepared based on the prompts in the content representation (CoRe) (Loughran et al., 2006) and the Turkish high school chemistry curriculum (Ministry of National Education, 2013). Interviews about the mixtures unit were conducted a few days before the teachers started to teach the unit. Interview questions were intended to elicit how the participants planned to teach the mixtures unit.

The teachers led two hours of chemistry classes for 10th grade students each week. The classes were either two consecutive hours in a day or one hour each on two different days depending on the teacher's schedule. Weekly interviews were conducted after the final class of the week to elaborate the salient teaching and learning activities of the lesson. During the interviews, the teachers were asked to discuss the reasons for using certain activities during the instruction. For instance, if the teacher used a demonstration in the lesson, the reason for using that demonstration and whether s/he believed it was used successfully were asked during the interview.

Participant observation. Non-participant observations were used while observing participant teachers’ instruction. Thus, the researcher was a complete observer (Fraenkel and Wallen, 2006) and was not involved in the teaching process. In the current study, the first author was the observer. She is a chemistry educator who has studied teacher education, specifically PCK, for more than ten years. The researcher began to attend classes two weeks before starting to collect data to help students and in-service teachers adjust to her presence in the teaching environment. Field notes were taken during the observations. Simultaneously, a digital audio recorder was used to avoid missing any conversation during the instruction.

Data analysis

All audio-recordings of the interviews and class observations were transcribed before data analysis. Data obtained from interviews, observations, and field notes were analysed using a deductive approach (Patton, 2002). A colleague studying PCK coded some of the data to check whether discrepancies existed between the coders. Inconsistent sections were discussed until a consensus was reached by the coders.

The data obtained for the components of PCK were analysed deductively. In deductive analysis, the collected data are analysed using an already existing framework (Patton, 2002). In this study, a modified version of the PCK model proposed by Magnusson et al. (1999) was used as the existing framework (see Table 1) to analyse data deductively. The interactions between STO and the other components of PCK were then analysed. Before starting the analysis of interactions, a coding scheme was prepared by the researchers based on the related literature. The analysis was then conducted regarding interactions according to this coding scheme. Detailed information about the data analysis procedure is presented in Table 3.

Table 3 Coding scheme used to determine interactions between STO and the other components of PCK
STO KofL KofIS KofC KofA
Beliefs about the purposes of science teaching The teacher considers students’ pre-requisite knowledge, learning difficulties and misconceptions related to his/her beliefs about the purposes of science teaching The teacher uses an instructional strategy which supports him/her to emphasize his/her beliefs about the purposes of science teaching The teacher benefits from his/her repertoire of curriculum while teaching his/her goals and purposes of science teaching The teacher assesses students’ learning considering his/her goals and purposes of science teaching
Beliefs about science teaching and learning The teacher considers students’ pre-requisite knowledge, learning difficulties and misconceptions related to his/her beliefs about science teaching and learning The teacher uses an instructional strategy which supports him/her to emphasize his/her beliefs about science teaching and learning The teacher considers curriculum referring to his/her beliefs about science teaching and learning The teacher assesses in a way supporting his/her beliefs about science teaching and learning
Beliefs about the nature of science The teacher considers students’ pre-requisite knowledge, learning difficulties and misconceptions related to his/her beliefs about the nature of science The teacher uses an instructional strategy which supports him/her to emphasize his/her beliefs about the nature of science The teacher considers curriculum related to the nature of science The teacher makes an assessment supporting his/her beliefs about the nature of science


At the end of the analysis, related interviews and observation data were translated into English by the researchers. A philologist examined the translation to confirm that it was appropriate.

Data analysis of science teaching orientations. The first dimension, beliefs about the purposes of science teaching, was analysed using the curriculum emphasis model proposed by Roberts in 1982. Roberts (1982) examined the curricula implemented in North America and found seven curriculum emphases in the history of science education: everyday coping, structure of science, science technology and decisions, scientific skill development, correct explanations, self-as-explainer, and solid foundation. In Appendix A, each of the seven curriculum emphases stipulated by Roberts (1988) was described regarding the view of science, the view of learners, the view of teachers, and the view of society. Friedrichsen et al. (2011) suggested that the description of each curriculum emphasis “includes elements of the nature of science, goals of science education, and views of teaching and learning” (p. 371). Therefore, these curriculum emphases could be used to explore teachers’ beliefs regarding the purpose of the curriculum they teach (van driel et al., 2008; Friedrichsen et al., 2011). In this study, we considered the view of science as the basis to determine teachers’ beliefs about the purposes of science teaching (see Appendix A).

The second dimension, beliefs about science teaching and learning, was analysed using the categorisation proposed by Luft and Roehrig (2007). Luft and Roehrig developed the Teacher Beliefs Interview (TBI) to capture teachers’ beliefs about science teaching and learning. Responses to the interview questions related to the participants’ beliefs about science teaching and learning science were analysed considering teacher- and student-focused beliefs suggested by Luft and Roehrig (2007) (see Appendix B for categories and descriptions).

The other components of PCK, KofL, KofC, KofIS, and KofA, were analysed deductively considering the modified version of Magnusson et al.'s (1999) PCK model (see Table 1).

Data analysis of interactions between STO and the other PCK components. To analyse interactions among the sub-components of STO and KofL, KofC, KofIS, and KofA, a coding scheme (see Table 3) was prepared using studies in the literature (Padilla and Van Driel, 2011; Park and Chen, 2012; Aydin and Boz, 2013). The coding scheme was used to elicit the interactions between PCK components. Arguments made in the Results section were then manifested considering the prominent properties of the interactions.

When analysing the interactions, both the researcher's observations and interviews with the teachers were taken into consideration. In order to be considered as an interaction, the actions of the teachers had to be observed by the researcher during the instruction, as well as confirmed by the teachers during the interviews. For instance, if the teacher thinks that using analogies is a good way to increase students’ understanding and uses it in the class, then there is an interaction between the teacher's beliefs about science teaching and learning, which is a sub-component of STO, and the teacher's knowledge of topic-specific representations, which is a sub-component of KofIS.

Regarding the third dimension of STO, which is beliefs about the NOS, no data were gathered from the observations. Due to the lack of data, no interactions could be detected considering beliefs about the NOS. Therefore, it was not included in the study.

Validity and reliability issues of this study

In this study, prolonged engagement, persistent observations, triangulation, and member checking were used to provide credibility (Lincoln and Guba, 1985). The first author began to attend the classes regularly and spent time with the participant teachers and students two weeks before starting the observations. For the following two months, she continued to observe the mixtures unit for two class hours a week with the same students. She spent time with the teachers outside of class hours at the school, either at the laboratory or in the teachers’ rooms. This ensured prolonged engagement and persistent observations. A triangulation of sources was provided by using different kinds of data sources such as interviews, observations, and field notes to examine the same phenomenon. Analyst triangulation was ensured by asking two colleagues to analyse some of the data by providing them transcribed documents of the interviews and observations. These colleagues were also studying PCK. Member checking was provided by discussing the emerging findings with the participants throughout the study and at the end of the study. For this purpose, the findings that emerged were provided to the participants and they provided comments to understand whether the participants agreed with the authors’ conclusions.

In this study, the first author was a complete observer as a researcher (Patton, 2002). She attended the classes and did not participate in any kind of instructional activity during class hours; she only observed the classroom and took notes.

Ethical considerations

Before starting the study approval from the Institutional Review Board (IRB) was obtained to conduct a study with in-service chemistry teachers working in the high schools of the Ministry of National Education (form number: 14588481/605.99/3997621). All participants were informed about the purpose of the study and that they were free to withdraw at any time they wanted. The participant teachers voluntarily involved in the study and pseudonyms were used for the participants.

Results

In this part, the ways in which in-service chemistry teachers’ STO interacted with their PCK are given with seven specific arguments. The STO of Mete and Ece were examined under two dimensions: beliefs about the purposes of science teaching and beliefs about science teaching and learning. First, regarding their beliefs about the purposes of science teaching, Mete and Ece held the same purposes: everyday coping (i.e., students utilise science to explain the reason for everyday events), solid foundation (i.e., students use science to be successful in their exams or next classes) and correct explanations (i.e., students learn the best possible explanation of science concepts or events). Regarding their beliefs about science teaching and learning, both participants had teacher-focused beliefs. Beliefs about the NOS were not included because no concrete emphasis of the NOS was observed by the researcher during the instruction. KofL, KofC, KofIS, and KofA were examined under the sub-components given in Table 1.

Interactions between beliefs about the purposes of science teaching and the other components of PCK

The ways in which teachers’ beliefs about the purposes of science teaching and the other components of PCK interacted were provided under four arguments.

Argument 1: When correct explanations and solid foundation purposes interacted together with the same PCK component, solid foundation appeared to be the reason for having correct explanations purposes.

Correct explanations (STO) and solid foundation (STO) purposes together interacted with the following sub-components: misconceptions (KofL), subject-specific instructional strategies (KofIS), and the purpose of assessment (KofA). When these interactions were examined in detail, we found that the participants tried to use correct explanations (e.g. giving the best possible scientific explanation about chemistry concepts) due to their solid foundation purposes (e.g. wanting students to be successful in exams). In this part, interactions with misconceptions and the purpose of assessments were given. Information about subject-specific instructional strategies was presented together with the second argument.

Mete held solid foundation and correct explanations purposes, which interacted with his knowledge of students’ misconceptions. Mete was aware of his students’ possible misconceptions related to the mixtures unit; however, during the interview about PCK components, he claimed that he did not expect students to have misconceptions about the mixtures unit, as this unit was highly related to events that they encounter in their daily life. It was interesting that even though he did not expect students to have misconceptions, he placed importance on eliminating students’ possible misconceptions and emphasising the correct explanations of the misconceptions. Whether or not a misconception was detected in class, Mete provided the scientific explanations of potential misconceptions just in case.

“A solution containing undissolved solute is a saturated solution; not a supersaturated one… Every solution that is in equilibrium with undissolved solute is a saturated solution. Sometimes I draw a solution (on the board) that is in equilibrium with undissolved solute and ask the type of the solution. Students immediately respond it as supersaturated solution, which is wrong.”

As was clear from Mete's explanation, he explained how a saturated solution differed from a super-saturated one, which could be a misconception. During the weekly interview, he was asked about his reason for explaining the correct form of this possible misconception. He responded, “If students have these misconceptions, they will be eliminated when I explain the correct form. So that they can respond to the questions correctly if asked in the nationwide examinations.” From this explanation, it was understood that he explained the correct form of misconceptions because he wanted to support his students’ understandings. This would allow them to achieve high scores on their examinations which is compatible with his solid foundation beliefs. As a result, Mete's correct explanations and solid foundation purposes interacted with his knowledge of students’ misconceptions and his reason for having the correct explanations purpose was his solid foundation purpose. Ece shared the same reasons with Mete while giving scientific explanations of chemistry concepts. She tried to improve her students’ chemistry knowledge to help them achieve high scores on their exams. Therefore, it can be concluded that Ece held correct explanations and solid foundation purposes together, which interacted with her knowledge of students’ misconceptions.

Besides the knowledge of their students’ misconceptions, Mete's and Ece's correct explanations and solid foundation beliefs interacted together with their purposes of assessment in which solid foundation was the reason for having correct explanations. During the instruction, both Mete and Ece placed importance on solving problems or focused on answering questions related to the topic covered. In a weekly interview, Mete stated:

“When we solve problems about the topic covered, students understand what kinds of questions may be asked in the HEE and UPE about this topic, and it also allows us to review and summarise the topic. It enables me to detect how much students learn, find the missing knowledge, and fill in the gaps.”

From this explanation, it was understood that Mete gave importance to finding students’ misunderstandings and filling the gaps, which is consistent with his correct explanations purpose because it was important for him to give the best possible explanation of the topic.

Questions asked on the nationwide exams are in a multiple-choice format. While giving examples of these kinds of questions, no matter what the type of the question was, Mete always answered the first question or solved the first problem and then encouraged students to answer the rest. In particular, while answering the multiple-choice questions, he explained the questions in detail and wanted students to learn the correct answers to the questions. In his explanations, it was clear that he intended to emphasize the types of questions that may be asked at the HEE and UPE. During his instruction, Mete always emphasised and reminded students how chemistry content may be included in questions on these nationwide examinations. From the above explanations, it was clear that Mete's correct explanations and solid foundation purposes dominated his knowledge of assessment.

Similar to Mete, during a weekly interview, Ece claimed, “It would be better for students to be familiar with the questions that will potentially be asked in the exams. Therefore, I place importance on solving these kinds of questions in class and assign similar questions as homework.” When she delivered multiple choice tests to the students as homework, she checked them to be sure that students worked on them. She also wanted students to ask questions about problems they had difficulty solving or understanding in the homework so that she could explain the correct solution. In this way, she eliminated any kind of misunderstanding and filled in students’ missing knowledge about the topic. In light of the explanations above, it may be stated that when Mete's and Ece's correct explanations and solid foundation purposes interact with their purposes of assessing students’ understanding, their solid foundation purposes are the reason for their correct explanations purposes.

Argument 2: Teachers’ preferred instructional strategies interacted with their solid foundation and correct explanations purposes.

Mete and Ece always used didactic teaching in their classes. While Mete's beliefs about the purposes of science teaching interacted only with using subject-specific instructional strategies, Ece's beliefs interacted with using subject-specific strategies and topic-specific representations. Both teachers asserted their solid foundation (e.g. getting high scores on exams) and correct explanations (e.g. explaining a question correctly) beliefs as their reasons for using didactic teaching. Moreover, solid foundation beliefs were the reason for their correct explanations beliefs, as is discussed in argument 1. Mete claimed that he used didactic teaching to support his students’ success in the examinations. He stated:

“As a teacher, you are expected to be a guide to the students and students are expected to be active participants in the classes. However, in this way, students cannot succeed in the exams. They can learn the subject but if you (the teacher) don’t explain every single detail about the unit, they fail in the exam. Therefore, you don’t want them to actively participate in the lesson and you perform didactic teaching personally.”

The above explanation indicates the interaction between Mete's didactic teaching approach and beliefs about the purposes of science teaching (solid foundation and correct explanations). He believed that students could learn chemistry content by taking active roles during classes. However, this would not be sufficient to allow the students to achieve high scores on their exams. The teacher can explain important concepts, which are important for getting high scores on exams, better than anyone. Therefore, students should listen to their teachers to get high scores on their exams.

Ece also had correct explanations and solid foundation beliefs about the purposes of science teaching. She used didactic teaching in her instruction and stated that she could not give students the opportunity to participate in the instruction because of overpopulated classrooms. She explained:

“I don’t allow students to participate actively in class. Since the classes are overpopulated, if I let them participate and ask questions, do the demonstrations, or solve questions, what if they do it wrong? I will lose at least 10 minutes in correcting it. For this reason, I usually do everything so that I do not lose time. This is to prevent students from failing in the exams as much as possible.”

Ece taught in a didactic way so that students would not misunderstand the content. She believed she would waste time if students failed to solve the questions correctly, which would lead them to cover fewer questions. Thus, as a teacher and the authority, she solved the questions correctly for students. In this way, she did not lose time or have to correct any errors. As a result, both teachers’ beliefs about the purposes of science teaching interacted with their use of didactic teaching methods in their instruction.

When we consider teachers’ use of topic-specific representations, only Ece's beliefs about the purposes of science teaching and topic-specific representations interacted. She placed importance on the nationwide examinations. Therefore, she always warned her students to be careful about the possible questions on these examinations. As an example, while she was explaining the use of solubility vs. temperature graphs, she projected the solubility vs. temperature graph of potassium nitrate (KNO3) on the board. She then stressed what kinds of questions could be asked in the HEE and UPE related to these kinds of graphs. She stated:

“Now, look at the graph. You see, there are many temperature values in the graph. Let's mark 20 °C in order to write a question. Listen to me carefully, these kinds of questions may be asked in the exams. The solubility of KNO3 is 30 grams at 20 °C. Can we find the solubility of it at 40 °C by using the proportion?”

During her introduction of solubility–temperature graphs, she warned students that in their examinations, they may come across the type of mathematical problem she displayed. She tried to familiarize her students with these questions to prepare them for the exams. This was consistent with her solid foundation purposes.

Argument 3: Teachers altered the curriculum only if they believed it would lead students to achieve better scores in their examinations.

Both Mete and Ece had solid foundation purposes that interacted with altering the curriculum. Even though they were not stated as goals or objectives in the curriculum, Mete taught the students chemistry topics like vapour pressure, the common ion effect, and problems about solubility. When he was asked about his reasons for solving problems about solubility even though it was not stated in the curriculum, he answered:

“I usually don’t go beyond the limits of the curriculum, but sometimes I teach concepts that are not included in the curriculum, because I believe that students will use them somewhere in their future lives, maybe in the exams, maybe in college classes, I don’t know.”

His reason for teaching topics that were not included in the curriculum was his solid foundation purposes. He altered the curriculum because of his purpose to prepare students for future chemistry classes. He covered topics that he was not required to cover in 10th grade classes because he believed that he could help his students be successful in their future classes.

Similar to Mete's, Ece's beliefs about the purposes of science teaching interacted with her alterations of the curriculum. Consistent with her solid foundation beliefs, she wanted her students to be successful in the nationwide examinations. For this purpose, even though they were not stated as goals or objectives in the curriculum, she taught her students extra topics and concepts because she thought questions about these topics or concepts might be asked in the examinations. She explained the reason for covering such topics although they were not stated in the chemistry curriculum in a weekly interview as follows:

“For instance, let me give an example from the last unit we covered, Acids–Bases and Salts. Topics related to the acid–base reactions and their relation to the mole concept are not given importance in the curriculum. However, all of the test books cover them and there are questions in the test books about these topics. Therefore, in order to help students respond to the questions in the test books, I sometimes extend the limits of the curriculum and teach other topics.”

Ece's explanation clarifies her goal of supporting her students’ understanding to enable them to be successful in their exams. In order to help them easily solve questions, she covered topics that were beyond the limits of the curriculum. This allowed her students to develop the ability to solve every question about topics that are not stated in the curriculum but that are covered in the test books. As a result, regarding Mete's and Ece's explanations and instruction, it can be stated that their beliefs about the purposes of science teaching interacted with their alterations of the curriculum.

Argument 4: What teachers assessed is related to their correct explanations and everyday coping beliefs, while the way they assessed is related to their solid foundation beliefs.

Mete's and Ece's everyday coping and correct explanations beliefs interacted with what they assessed about students’ learning. Most of the time, they assessed students’ knowledge of chemistry content and their daily life applications of the chemistry concepts they taught.

During classes, Mete always encouraged students to learn about the daily life applications of the topic they covered. If students did not have many ideas about daily life examples, he explained them. He thought that learning daily life applications of a chemistry concept helped students learn meaningfully and prevented them from forgetting the concept. Therefore, he found it important to assess whether his students learned the daily life usages of chemistry concepts. Ece's approach was similar to that of Mete; she found it important to emphasise the daily life applications of chemistry topics. For this purpose, she asked students to provide examples of daily life events related to the chemistry topic or to ask questions about the reasons for these events to gage students’ knowledge. Sometimes, she used daily life events to stress chemistry topics. For instance, she asked, “If I give an example from daily life, let's say there is a 20% discount on all of the products in a store. Does this mean that I will get 20 TL off if I buy a shirt?” to emphasise how percent is used in mathematics. Some of the students responded “yes,” while others responded “no.” She then explained the correct answer and switched to teaching mass percent concentration, stating, “It is exactly the same in chemistry. If you want to prepare a 20% sugar solution you have to use 20 grams of sugar and 80 grams of water.” This is an example of Ece's everyday coping purposes, as well as her correct explanations purpose regarding science teaching and learning. Even though she received answers from students, she did not let students defend their ideas and provided the correct explanations of the question by herself. While solving problems in class with students, she only received answers from students and proceeded to solve the problem by herself on the board. Similar to Ece, Mete also found it important to provide the correct explanations of the answers. When he asked students questions, he always repeated the correct answers and wanted students to learn the best possible answer to the question. Most of the time, while solving problems in the class, he solved the problems first, and then asked students to solve the rest of the questions. From these examples, we can conclude that both Mete's and Ece's everyday coping and correct explanation purposes interacted with what they assessed in the classes.

Mete's and Ece's solid foundation purpose had an interaction with their methods of assessment. They used multiple choice questions in classes to show students how chemistry concepts could be asked in exam questions because they wanted to familiarize their students with the HEE and UPE. They also assigned multiple choice tests as homework for students. Mete explained his reason: “the type of questions used in nationwide examinations is multiple choice and I want [students] to see how the chemistry content we cover in the classes can be asked as a question.” Ece used multiple choice questions for the same purpose consistent with her solid foundation purposes. For instance, she always reminded students about the types of questions that may be asked in the HEE and UPE. Her reminder was “be careful. In previous years, questions with graphs were widely used in the examinations, like this one (pointing to a question with a graph). Who wants to solve this question?” Regarding these explanations, teachers’ beliefs about the purposes of science teaching interacted with the ways in which they assessed their students’ understanding.

Interactions between beliefs about science teaching and learning and the other components of PCK

The interactions between teachers’ beliefs about science teaching and learning and the other components of PCK were provided under three arguments.

Argument 5: Beliefs about science teaching and learning interacted with all the sub-components of KofIS.

Mete and Ece used traditional didactic teaching; they did not use any subject-specific teaching method and they had teacher-focused beliefs about science teaching and learning. Mete defined his ordinary instruction:

“First, I verbally introduce the chemistry concept that I want to emphasise. I write it on the blackboard and then solve problems about the concept. If there are visuals or videos of experiments related to the concept, I show them to the students. The teacher is the one who compiles and summarises the subject for the students.”

His description of ordinary instruction makes it clear that this instruction had the features of didactic teaching. Thus, his teacher-focused beliefs about science teaching and learning were consistent with using the dominant teaching method, which was lecturing. Like Mete, Ece used direct instruction methods during her classes. She explained the concepts, important points, and definitions and gave examples about the topic in focus. She spoke at least 15 minutes without interruption in every class. She frequently warned students to listen to her carefully. These actions were compatible with her teacher-focused beliefs about science teaching and learning. Considering these explanations, both Mete's and Ece's beliefs about the purposes of science teaching and learning interacted with their chosen teaching methods.

Considering topic-specific activities, conducting experiments is a widely conducted activity in chemistry education. Mete believed that laboratory experiments were useful for increasing students’ understanding of chemistry; however, he did not use them actively in classes. He explained:

“Effective instruction is related to how many senses of students you appeal to as a teacher. The importance of conducting laboratory experiments comes from this principle. If we are talking about chemistry or physics, using the laboratory is obligatory if possible. However, I show videos of experiments via the Internet. In this way, students can also learn what they need to learn.”

Mete's reason for using videos of experiments instead of conducting them in the laboratory was to avoid wasting too much time in classes; he explained this situation as:

“There are many videos of experiments conducted and recorded by large education companies that you can retrieve quickly online without wasting time. It takes too much time to conduct an experiment with your students in the laboratory. If you do [conduct an experiment], you will fall behind schedule.”

From these explanations, it was obvious that Mete thought that using laboratory activities to increase students’ understanding was important. However, he claimed that he could not conduct experiments in the laboratory with students due to time limitations. His teacher-focused beliefs led him to show the videos of the experiments via the Internet, and he tended to place the same value on students watching the videos of experiments and doing experiments by themselves. Hence, his teacher-focused beliefs interacted with his use of topic-specific teaching strategies.

Unlike Mete, Ece used scientific demonstrations during instructions when necessary. She shared Mete's teacher-focused beliefs about science teaching and learning. Her use of demonstrations in class was consistent with her teacher-beliefs. For instance, when she wanted to use demonstrations, she generally prepared the materials with the help of a student and then performed the demonstration. She did not let students participate in the experimental activities or do the activities by themselves. She attributed not letting students participate in the activities to the issues of the overpopulated classroom. While performing the demonstrations, she explained the theory behind them and asked the students questions. In brief, she led the demonstrations herself. Thus, it was clear that there was an interaction between both Mete's and Ece's beliefs about science teaching and learning and their use of topic-specific activities.

Focusing on the teachers’ use of topic-specific representations, it was clear that Mete widely used representations such as analogies and symbolic representations like graphs, molecular representations, and schemas to increase students’ understanding of chemistry. However, he used them without involving students in the process or without completely considering whether the students understood the experiment. For instance, he used analogies superficially without considering the possibility of causing misconceptions because of ill-defined explanations, or he drew graphs by himself on the board and explained how to interpret these graphs. However, he did not care about whether students were able to draw similar graphs. He always taught the topic by himself and assumed that students had learned it. Therefore, there was an interaction between his use of topic-specific representations and his beliefs about science teaching and learning. Considering his teacher-focused beliefs, it was not surprising to see him taking the lead when using representations. In one of the interviews conducted after the instruction, the following dialogue between the researcher and Mete occurred:

“R: You often use analogies during your instruction. What is the purpose of using analogies?

Mete: So that they [students] can understand better. Establishing similarities with what they are familiar will lead them to understand clearly.

R: What about the graphs? Most of the time you draw the graphs related to the topic on the board.

Mete: It is because I want them to learn the relationship between the variables on the related axes [of the graphs].

R: Do you think it is beneficial for their learning?

Mete: Sure. If they listen carefully, they can easily learn.”

In his explanation, Mete stated that he believes students can learn if they listen to the teacher. It appeared that he was not interested in what students understand or misunderstand about the concepts being taught. In particular, when using analogies or other types of representations in chemistry, there is always a chance that students will misunderstand abstract concepts. However, Mete believed that if students did not understand a concept, they could ask the teacher, who would explain the concept again and again until students understand.

Considering Ece's teacher-focused beliefs about science teaching and learning, there appeared to be an interaction between her beliefs about science teaching and learning and topic-specific representations. She frequently used analogies and graphs during her instruction. However, her way of using these topic-specific representations was teacher-focused, similar to her beliefs about science teaching and learning. She drew analogies by herself and did not consider whether students understood them or not, like Mete. Likewise, she used graphs and explained to students how to interpret them. However, she did not ask students to be involved in the process; instead, she did all the work by herself. This indicated an interaction between teachers’ beliefs about science teaching and learning and their use of topic-specific representations.

Argument 6: There was an interaction between KofC and beliefs about science teaching and learning for the participant who was more knowledgeable about the curriculum.

During the interviews about participants’ KofC, it was detected that Mete was more knowledgeable than Ece. He stated that he knew all of the objectives, the sequence of the topics, and the restrictions of the curriculum by heart. However, Ece sometimes had difficulty in implementing the curriculum and needed to review it before classes. Regarding teachers’ KofC, while Mete's beliefs about science teaching and learning interacted with the sub-components of KofC, Ece's did not.

As a teacher, Mete managed classes as if he was the leader of the class; he attributed this attitude to the loaded and complex curriculum. When he was asked about the reasons for his teacher-focused instruction and his lack of recognition of students’ ideas during instruction, he claimed:

“There are 2 hours for chemistry lesson in a week in 10th grade; however, the curriculum is too loaded, complex, and verbal. It is impossible to meet all the objectives stated in the curriculum without taking the leadership on, so what you do as a teacher is find ways to meet the objectives by ignoring students’ voices.”

From this explanation, it was clear that Mete was aware of all of the objectives stated in the curriculum and that he aimed to teach these objectives to his students. However, his teacher-focused beliefs manifested due to the time limitation. Hence, an interaction occurred between his beliefs about science teaching and learning and his knowledge of the goals and objectives of the curriculum. Therefore, to deal with the goals and objectives related to topics, he takes the lead of the instruction, corresponding to his teacher-focused beliefs about teaching.

When we consider Mete's use of the curriculum, we may say that he generally considered the limits of the curriculum. However, he did not hesitate to teach concepts that were not stated in the curriculum when he felt that they would help students better understand future topics. In order to maximise students’ understanding, he decided to reorganise the topics in a way that he believed would help his students better understand the material according to his past experiences. He said that he would not eliminate any topic in the curriculum, but he would add some if necessary. He gave vapour pressure and boiling point concepts as an example of the issue.

“According to the curriculum objectives, while vapour pressure is not required to be taught, boiling point is. The effect of salt dissolved in water to vapour pressure is not required to be taught, but boiling point elevation is. There is a contradiction here. How can I teach boiling point without teaching vapour pressure, partial vapour pressure, and their relationship to the amount of dissolved particles?”

When he was asked about his reason for teaching vapour pressure even though it was not required to be taught according to the curriculum, he responded:

“I think it will be hard to understand boiling point elevation unless [students] learn vapour pressure. According to the curriculum, I am supposed to mention boiling point elevation, freezing point depression, and osmotic pressure. But if I try to teach them without teaching vapour pressure first, it will be problematic.”

In light of these explanations, it may be concluded that there is an interaction between Mete's teacher-focused beliefs about science teaching and learning and altering the curriculum.

Argument 7: Teacher-focused science teaching and learning beliefs prevent teachers from focusing on students’ prerequisite knowledge, learning difficulties, and misconceptions.

Mete had teacher-focused teaching and learning beliefs. There was an interaction between his teacher-focused beliefs and his knowledge of students’ prerequisite knowledge. He assumed that students had to have prerequisite knowledge about the new unit if he covered a topic that was prerequisite to the new unit. For instance, while explaining acids and bases as polar solutes, he told students, “As we have already covered the acids and bases unit, you are supposed to know all this stuff because you have to.” Likewise, while teaching vapour pressure, he asked the students to define vapour pressure, and nobody could define it; in response, he said, “As far as I remember, you wrote it down in your notebook. So why can’t you define it?” From these examples, it can be claimed that Mete's beliefs about science teaching and learning interacted with his knowledge of students’ prerequisite knowledge.

Consistent with his teacher-focused beliefs, Mete did not expect students to have much difficulties in learning about mixtures because he stated, “The unit is covered in middle school, so [students] don’t have much difficulty with this unit.” If students do not ask questions, Mete assumes that they understand the subject. For him, delivering the information was enough to enable students to understand the topic. For quite similar reasons to those stated by Mete, Ece did not expect her students to have difficulties in learning the mixtures unit. Thus, as a result of Mete's and Ece's actions, which were consistent with their teacher-focused beliefs, it can be stated that there was an interaction between teachers’ beliefs about science teaching and learning and their knowledge of students’ learning difficulties.

Mete did not bother to check whether students have misconceptions during classes; he assumed that students did not have any misconceptions because they were familiar with the mixtures unit from their daily life. He ignored the views of students and considered his own views regarding the misconceptions of students. Even though he did not presume that students had misconceptions in the mixtures unit or detect them in classes, most of the time he gave the correct explanations for these misconceptions. For instance, as was mentioned before, even though no student asked the relevant question, he explained that a solution containing undissolved solute is not a supersaturated but saturated solution. He always explained the correct form of misconceptions before they were detected or asked by students. His manner of ignoring students’ ideas was consistent with his teacher-focused beliefs about science teaching and learning and interacted with his knowledge of students’ misconceptions.

Discussion and conclusions

This study revealed that when participant teachers’ solid foundation and correct explanations purposes interacted together with the same PCK component, solid foundation purposes appeared to be the reason for having correct explanations purposes. Roberts (1988) considered these two purposes as default emphases that are situated in traditional science curricula, and their message is mentioned implicitly. The message behind the correct explanations purpose is “Learn it because it's correct” (Roberts, 1988, p. 37), and the message behind solid foundation purposes is getting ready for the next classes and years. The role of the teacher who has the correct explanations purpose was explained by Roberts (1988) as “One responsible for identifying and correcting the errors in student thinking” (p. 45). When these explanations were combined with the results of this study, teachers’ purposes of preparing their students for nationwide examinations and trying to explain every single detail about a topic make sense. They wanted their students to learn the topic without missing any points to allow the students to succeed in their examinations. Therefore, their solid foundation purposes dominated their correct explanations purposes.

Another purpose held by the participant teachers of this study was everyday coping. There have been efforts to transfer chemistry curricula from the “traditional curriculum development process, which started (and still does in many countries) from the subject content and often finished there” (Childs et al., 2015, p. 34) to an alternative process which included students’ everyday experiences. Considering these efforts, including chemistry in everyday life in the curriculum may help teachers to hold everyday coping purposes for teaching chemistry.

Participants’ beliefs about the purposes of science teaching interacted with almost all the sub-components of KofL and KofA, while they interacted with a smaller number of sub-components of KofC and KofIS. Padilla and van Driel (2011) reported that teacher-focused orientations like didactic and academic rigor are generally linked to KofL and KofIS. Moreover, Park and Chen's (2012) study indicated that KofL and KofIS were elicited as the components that had the most interaction with the other components of PCK, while KofC and KofA interacted the least. In the current study, participant chemistry teachers’ KofA demonstrated a contradiction with previous studies. All the sub-components of KofA interacted with the beliefs about the purposes of science teaching together with KofL. When the interactions between KofA and beliefs about the purposes of science teaching were examined deeply, it was found that solid foundation and correct explanations purposes dominated teachers’ KofA. When solid foundation and correct explanations interacted together with the same PCK component, solid foundation behaved as if it were also the reason for having correct explanations as a purpose. Participant chemistry teachers were strongly connected to the solid foundation purpose; they considered this purpose in any kind of instructional practice, including in assessing their students. Therefore, the interaction between their KofA and beliefs about the purposes of science teaching increases. When we focus on KofC, we can see that previous studies reported its weak interaction with the other components of PCK (Park and Chen, 2012; Aydin and Boz, 2013). Depending on the results of the present study, we may infer that the reason for the weak interactions between chemistry teachers’ KofC and other components of PCK is their beliefs about the purposes of science teaching, which is a sub-component of the overarching STO component (Magnusson et al., 1999). Teachers’ KofC was controlled by their beliefs about the purposes of science teaching. The participants of this study had everyday coping, solid foundation, and correct explanations beliefs. In particular, their solid foundation purposes direct their KofC; they focus more on students’ preparation for nationwide examinations or their future chemistry classes. To this aim, they sometimes avoided or altered the objectives stated in the curriculum to make them suitable to their own solid foundation purposes even though they were aware of those objectives. Hence, beliefs about the purposes of science teaching and KofC did not interact much.

Park and Chen (2012) and Veal and Kubasko (2003) claimed that the teaching approaches teachers used were highly influenced by their STO. In this study, the teaching strategy that the teachers preferred to use during instruction interacted with their beliefs about the purposes of science teaching in terms of solid foundation and correct explanations. The teachers did not use any subject-specific topic strategy; instead, they used traditional didactic teaching throughout the teaching of the mixtures unit. They explained that their reason for using didactic teaching was to give students all the important information in order not to miss any single point. Therefore, students learned all the information they taught, and their chances of being successful in the nationwide examinations would increase. From these explanations, it was clear that their solid foundational and correct explanations purposes affected their use of teaching strategies. Topic-specific teaching strategies did not usually interact with beliefs about the purposes of science teaching. Only topic-specific representations interacted with solid foundation purposes, which were related to teachers’ intentions for their students’ success in the nationwide examinations. Friedrichsen et al. (2009) suggested that high-stakes tests have a limiting role in teachers’ preferences of instructional strategies. This argument is also supported by the findings of the current study.

The teachers in this study altered the curriculum only if they believed it would allow students to get better scores on the examinations, which was consistent with their solid foundation beliefs about the purposes of science teaching. When the teachers felt that they needed to change the sequence of the topics, they did not hesitate to do it, especially if their students’ learning would be affected in a positive way from this change. As proposed by Lee and Luft (2008), experienced teachers give importance to organising curriculum subjects according to students’ needs and are flexible towards changing situations in classes.

In the current study, the chemistry teachers’ teacher-focused beliefs about science teaching and learning interacted with KofIS. The interactions were examined, including all the sub-components of KofIS. Padilla and van Driel (2011) argued that teacher-focused orientations had connection with KofIS. Likewise, Park and Chen (2012) suggested that teacher-focused STO managed teachers’ KofIS and prevented its interaction with the other PCK components. Moreover, in Demirdöğen's (2016) study, beliefs about science teaching and learning were reported to interact mostly with teachers’ KofIS.

KofA was the component of PCK that interacted with beliefs about science teaching and learning less than the other components, even though it interacted with teachers’ beliefs about the purposes of science teaching more than the others. Earlier research reported that KofA had the least interaction with the other components of PCK (Padilla and van Driel, 2011; Park and Chen, 2012; Aydin and Boz, 2013). Considering the overarching identity of STO (Grossman, 1990) and the strong relationship between beliefs about the purposes of science teaching and KofA as one of the results of this study, it can be concluded that the reason for its weak interaction with the other components of PCK could be teachers’ beliefs about science teaching and learning. Their teacher-focused beliefs about science teaching and learning may inhibit the interaction of KofA with the other components of PCK.

KofA is one of the most important, albeit less-studied components of PCK (Abell, 2007; Padilla and van Driel, 2011). Apart from the fact that beliefs about science teaching and learning interacted with KofA the least, when we examine the interaction deeply, we can see that only one of its sub-components, assessment methods, indicated an interaction with chemistry teachers’ beliefs about science teaching and learning. The same results were presented by Aydin and Boz (2013): assessment methods were affected by chemistry teachers’ orientations.

The participants had teacher-focused beliefs about science teaching and learning. Most of the time, they assessed their students’ chemistry understanding using informal questioning or by solving questions with students in the classes. They believed that if students failed to give correct answers to the questions, this would indicate that they did not understand the topic. Regarding their teacher-focused beliefs about science teaching and learning, dominating the assessment procedure and not giving chances to students in this process would be understandable because their beliefs about science teaching and learning affected the way they assessed their students.

A new model of teachers’ professional knowledge and skills that included PCK was presented at the PCK Summit in 2012 (Gess-Newsome, 2015). In this model, the orientations and beliefs of teachers were removed from the PCK model and placed as a separate construct that mediated teachers’ practices by acting as amplifiers or filters to teacher learning. For instance, the participants of the current study believe that lecturing is the best method to enable students to understand chemistry subject matter. Therefore, they use didactic teaching and their beliefs act as filters for using alternative teaching methods. As another example, the participants sometimes go beyond the limits of the curriculum and add topics that are not mentioned in the curriculum because they believe that this will help students better understand the content. Additionally, they believe that nationwide exams are important for students’ future lives. Therefore, they sometimes teach topics that are not included in the curriculum to help their students achieve success on the nationwide examinations. In this case, their beliefs act as amplifiers to change the sequence of the topics.

In the current study, most of the time, participants’ teacher-focused beliefs led them to enact teacher-focused instruction; however, having teacher-focused beliefs did not always mean to have under-developed PCK. The study of Mavhunga and Rollnick (2016) elicited that teachers may have well-developed PCK, independent from their beliefs. A teacher holding student-focused (e.g. reform-based beliefs) or teacher-focused beliefs (e.g. traditional beliefs) may have solid PCK (e.g. using alternative teaching and assessment methods).

Implications

The participants of this study held content-specific purposes and teacher-focused beliefs regarding science teaching and learning, which may inhibit them from participating in reform-based activities in their instruction. As frequently stated, beliefs are complex structures (Friedrichsen and Dana, 2005) that are resistant to change (Nespor, 1987; Kagan, 1992). It is especially important to identify the beliefs of experienced teachers, who typically have more resistant beliefs (Luft and Roehrig, 2007), to see whether they can keep pace with reform-based education. For this purpose, the beliefs held by in-service teachers should be examined and made explicit. Without knowing what such teachers believe, it will be difficult to change their beliefs regarding reform-based practices.

The findings of the current study have a number of implications for in-service teacher education. Professional development activities that have a superior effect on teachers’ beliefs (Luft and Roehrig, 2007) would be helpful to elicit and change the STO of experienced chemistry teachers. For instance, the participant teachers of this study used didactic teaching methods widely in their instruction. The belief that served as their reason for using this method could be identified, and professional development courses that could change their habits of using this teaching method could be conducted. To this end, alternative teaching methods could be introduced to the teachers to help them understand the necessity of using alternative teaching methods instead of didactic teaching methods. Even if they use didactic teaching methods, chemistry teachers have chances to enrich their instruction through the use of demonstrations and experiments to emphasise macroscopic nature, animations, and simulations to focus on sub-microscopic nature, and figures, graphs and chemical equations to indicate the symbolic nature of chemistry.

Another example of the utilization of reform-based teaching practices could be in assessment procedures. This study indicated that teachers’ purposes of science teaching interacted with their KofA more than the other components of PCK. The results of the current study and similar studies could be considered to reveal the reasons for and possible consequences of these interactions. Considering the strong interaction between in-service teachers’ beliefs about the purposes of science teaching and KofA, introducing alternative assessment techniques to in-service teachers may be helpful in placing more reform-based practices in their instruction. For instance, using concept maps would help them assess students’ understanding in chemistry topics for which concepts are abundant. Moreover, it would be useful to see the relation between the chemistry concepts most of which are abstract.

As stated above, beginning teachers’ beliefs are more flexible and open to reform than those of experienced teachers. Conclusions could be drawn from the studies conducted with experienced teachers to ensure that precautions are taken before the beliefs of beginning teachers become robust, as it is difficult to change such beliefs once they have developed. Programs introducing reform-based practices and their concrete applications would be helpful for beginning teachers to develop more student-centred beliefs in their early years of teaching.

Implications for pre-service chemistry teacher education can be drawn from the results of this study. If there are more and complicated interactions between the components of PCK, the PCK of teachers becomes more developed (Park and Chen, 2012; Aydin et al., 2015). As the STO component dominates the instructional decisions of teachers, activities conducted in pre-service teacher education programs that lead to the development of pre-service teachers’ STO, and hence their PCK, would be beneficial. Well-designed university courses have a particularly important impact on the development of pre-service teachers’ STO (Avraamidou, 2013). Most of the time, chemistry teacher educators have focused on subject-specific and pedagogical courses. As a result, courses that have an effect on pre-service teachers’ beliefs have been neglected. Therefore, little changes in the STO of pre-service teachers were observed with the existing courses in teacher education programs (Brown et al., 2009). To enhance the use of reform-based teaching, courses focusing on teachers’ belief systems may be helpful for developing reform-based STO. By giving a wide coverage to designing and conducting experiments, which is indispensable in chemistry, future chemistry teachers could develop more science-based purposes such as structure of science and scientific skill development. Likewise, courses enriched with the components of PCK would be beneficial to develop pre-service teachers’ PCK. If teachers have the opportunity to learn what PCK is and use it in an effective way with all components integrated, the quality of their teaching and learning activities will increase.

The participants of this study widely used traditional teaching methods and did not emphasise the NOS aspects during their teaching. Beginning in the pre-service chemistry teacher education program, more importance is given to subject-specific courses (e.g. analytical chemistry, organic chemistry), and most of the time, the nature and history of science are neglected. As a result, most in-service chemistry teachers did not give equal importance to the NOS and subject-specific topics. Therefore, starting from pre-service chemistry teacher education programs and continuing with professional development courses, the importance of focusing on the NOS aspects should be emphasised to teachers to enable them to concentrate on these aspects in their instruction. The rich structure of the history of chemistry would be helpful to chemistry teachers in this regard.

This study showed that in-service chemistry teachers mostly had everyday coping, correct explanations, and solid foundation purposes. They did not have other purposes proposed by Roberts (1988) such as structure of science, scientific skill development, and self-as-explainer. Their purposes were mostly related to teaching subject matter in a scientifically correct way by including everyday life knowledge to enable students to be successful in their future lives. Different from these content-based purposes chemistry teachers should have more science-based purposes that could utilise from experimental practices, to widen the world of students regarding chemistry teaching. For this purpose, during pre-service teacher education programs, pre-service chemistry teachers should spend adequate and effective time in chemistry laboratories. It would be helpful for them to develop more science-based purposes such as structure of science and scientific skill development.

The results of this study imply that nationwide examinations influenced in-service chemistry teachers’ beliefs, teaching orientations, and practices. Exam-oriented educational systems put pressure on teachers to prepare students for such exams. Therefore, a chemistry teacher's main purpose becomes preparing students for exams rather than developing scientific inquiry and literacy. Policy makers and chemistry educators should be aware of the burden on teachers and develop policies to overcome this issue.

Conflicts of interest

There are no conflicts to declare.

Appendix A Four curriculum commonplaces inherent in even curriculum emphases for science education (Roberts, 1988)

Curriculum emphasis View of science View of learners View of teachers View of society
Everyday coping A meaning system necessary for understanding and therefore controlling everyday objects and events Needs to master the best explanations available for comfortable, competent explanation of natural events, and control of mechanical objects and personal affairs Someone who regularly explains natural and man-made objects and events by appropriate scientific principles Autonomous, knowledgeable individuals who can do mechanical things well, who are entrepreneurial, and who look after themselves are highly valued members of the social order
Structure of science A conceptual system for explaining naturally occurring objects and events, which is cumulative and self-correcting One who needs an accurate understanding of how this powerful conceptual system works Comfortably analyzes the subject matter as a conceptual system, understands it as such, and sees the view point as important Society needs elite, philosophically informed scientists who really understand how that conceptual system works
Science, technology, decisions An expression of the wish to control the environment and ourselves, intimately related to technology and increasingly related to very significant societal issues Needs to become an intelligent, willing decision maker who understands the scientific basis for technology, and the practical basis for defensible decisions One who develops both knowledge of and commitment to the complex interrelationships among science, technology, and decisions Society needs to keep from destroying itself by developing in the general public (and scientists as well) a sophisticated, operational view of the way decisions are made about science-based societal problems
Scientific skill development Consists of the outcome of correct usage of certain physical and conceptual processes An increasingly competent performer with the processes One who encourages learners to practice at the processes in many different contexts of science subject matter Society needs people who approach problems with a successful arsenal of scientific tool skills
Correct explanations The best meaning system ever developed for getting at the truth about natural objects and events Someone whose preconceptions need to be replaced and corrected One responsible for identifying and correcting the errors in student thinking Society needs true believers in the meaning system most appropriate for natural objects and events
Self as explainer A conceptual system whose development is influenced by the ideas of the times, the conceptual principles used, and the personal intent to explain One who needs the intellectual freedom gained by knowing as many of the influences on scientific thought as possible Someone deeply committed to the concept of liberal education as exposing the grounds for what we know Society needs members who have had a liberal education – that is, who know where knowledge comes from
Solid foundation A vast and complex meaning system which takes many years to master in An individual who wants and needs the whole of a science, eventually One who is responsible for winnowing out the most capable potential scientists Society needs scientists

Appendix B Teacher Beliefs Interview category description (Luft and Roehrig, 2007)

Category Traditional (teacher-focused) Instructive (teacher-focused) Transitional Responsive (student focused) Reform-based (student focused)
Ways of maximizing student learning Teacher provides information in a structured environment Teacher monitors student actions or behaviors during instruction Teacher creates a classroom environment that involves the student Teacher designs the classroom environment to enable students to interact with each other and their knowledge Teacher depends on student responses to design an environment that allows for individualized learning
Role of the teacher Focus on information and structure Focus on providing experiences Focus on teacher/student relationships or student understanding Focus on collaboration between teacher and student Focus on mediating student prior knowledge and the knowledge of the discipline
Know when the students understand When they receive the information When they can reiterate or demonstrate what has been presented When they give an explanation or a response that is related to the presented information When they can utilize the presented knowledge When they can apply knowledge in a novel setting, or construct something novel that is related to the knowledge
What to teach, what not to teach Decision guided by adopted curriculum or other school factors Decision based on teacher's focus/direction Decision in which some modification is based on student feedback Decision based on student feedback and other possible factors Decision based on student focus and guiding documents (e.g., standards, research)
Deciding when to move on to a new topic Directed by teacher Directed by teacher; based on basic student understanding of facts and concepts Teacher decision based on limited student feedback or the ability of the teacher Decision based on student feedback that potentially involves revisiting concepts Decision based on an on-going evaluation and considers students’ abilities to demonstrate understanding in different ways. May involve the modification of lessons
Best way of learning science From the teacher By mimicking the teacher By using procedures/guidelines By encountering and interpreting phenomena By eliciting, encountering, and constructing their ideas about phenomena
Know when learning occurs Determined by the action of students during instruction. Emphasis is on order and attention as related to the student Determined through measures given by the teacher. Emphasis on the correctness of the student response to the measure Determined through subjective conclusions about the student Students interact with their peers or the teacher about the topic. Responses are limited or preliminary Students initiate significant interactions with one another and/or the teacher about the topic

References

  1. Abell S. K., (2007), Research on science teacher knowledge, in Abell S. K. and Lederman N. G. (ed.), Handbook of Research on Science Education, Mahwah, NJ: Lawrence Erlbaum, pp. 1105–1149.
  2. Abell S., (2008), Twenty years later: does pedagogical content knowledge remain a useful idea? Int. J. Sci. Educ., 30, 1405–1416.
  3. American Association for the Advancement of Science [AAAS], (1993), Benchmarks for Science Literacy: A Project 2061 Report. New York: Oxford University Press.
  4. Anderson C. W. and Smith E. L., (1987), Teaching science, in Richardson-Koehler V. (ed.), Educators’ handbook: a research perspective, New York: Longman, pp. 84–111.
  5. Avraamidou L., (2013), Prospective elementary teachers’ science teaching orientations and experiences that impacted their development, Int. J. Sci. Educ., 35, 1698–1724,  DOI:10.1080/09500693.2012.708945.
  6. Aydin S. and Boz Y., (2013), The nature of integration among PCK components: a case study of two experienced chemistry teachers, Chem. Educ. Res. Pract., 14, 615–624,  10.1039/C3RP00095H.
  7. Aydin S., Friedrichsen P. M., Boz Y. and Hanuscin D. L., (2014), Examination of the topic-specific nature of pedagogical content knowledge in teaching electrochemical cells and nuclear reactions, Chem. Educ. Res. Pract., 15(4), 658–674.
  8. Aydin S., Demirdogen B., Akin F. N., Uzuntiryaki-Kondakci E. and Tarkin A., (2015), The nature and development of interaction among components of pedagogical content knowledge in practicum, Teach. Teach. Educ., 46, 37–50,  DOI:10.1016/j.tate.2014.10.008.
  9. Baxter J. A. and Lederman N. G., (1999), Assessment and content measurement of pedagogical content knowledge, in Gess-Newsome J. and Lederman N. G. (ed.), Examining pedagogical content knowledge: the construct and its implications for science education, Hingham, MA, USA: Kluwer Academic Publishers, pp. 147–162.
  10. Boesdorfer S. B., (2012), PCK to practice: two experienced high school chemistry teachers' pedagogical content knowledge in their teaching practice, (unpublished doctoral dissertation), Illinois, USA: Illinois State University.
  11. Boesdorfer S. and Lorsbach A., (2014), PCK in action: examining one chemistry teacher's practice through the lens of her orientation toward science teaching, Int. J. Sci. Educ., 36, 2111–2132,  DOI:10.1080/09500693.2014.909959.
  12. Bogdan R. C. and Biklen S. K., (2007), Qualitative research for education, 5th edn, Boston, MA: Allyn and Bacon.
  13. Borko H. and Putnam R. T., (1996), Learning to teach, in Berliner D. C. and Calfee R. C. (ed.), Handbook of educational psychology, New York, NY: Simon & Schuster Macmillan, pp. 673–708.
  14. Brown P., Friedrichsen P. and Abell S. K., (2009), Do beliefs change? Investigating prospective teachers' science teaching orientations during an accelerated post-baccalaureate program, Paper presented at the European Science Education Research Association Conference, Istanbul, Turkey.
  15. Campbell T., Longhurst M., Duffy A. M., Wolf P. G. and Shelton B. E., (2013), Science teaching orientations and technology-enhanced tools for student learning in science, Res. Sci. Educ., 43, 2035–2057,  DOI:10.1007/s11165-012-9342-x.
  16. Childs P. E., Hayes S. M. and O’Dwyer A., (2015), Chemistry and Everyday Life: Relating Secondary School Chemistry to the Current and Future Lives of Students, Relevant Chemistry Education, Leiden, The Netherlands: Brill Sense,  DOI:10.1007/9789463001755_004.
  17. Cochran K. F., De Ruiter J. A. and King R. A., (1993), Pedagogical content knowing: an integrative model for teacher preparation, J. Teach. Educ., 44, 263–272.
  18. Demirdöğen B., (2016), Interaction between science teaching orientations and pedagogical content knowledge components, J. Sci. Teach. Educ., 27(5), 495–532,  DOI:10.1007/s10972-016-9472-5.
  19. Faikhamta C., (2013), The development of in-service science teachers’ understandings of and orientations to teaching the nature of science within a PCK-based NOS course, Res. Sci. Educ., 43(2), 847–869.
  20. Fletcher S. and Luft J. A., (2011), Early career secondary science teachers: a longitudinal study of beliefs in relation to field experiences, Sci. Educ., 95(6), 1124–1146.
  21. Fraenkel J. R. and Wallen N. E., (2006), How to design and evaluate research in education. New York: McGraw-Hill.
  22. Friedrichsen P. M., (2002), A substantive-level theory of highly-regarded secondary biology teachers’ science teaching orientations, (Doctoral dissertation), State College: The Pennsylvania State University.
  23. Friedrichsen P. and Dana T., (2005), A substantive-level theory of highly regarded secondary biology teachers’ science teaching orientations, J. Res. Sci. Teach., 42, 218–244,  DOI:10.1002/tea.20046.
  24. Friedrichsen P. J., Abell S. K., Pareja E. M., Brown P. L., Lankford D. M. and Volkmann M. J., (2009), Does teaching experience matter? Examining biology teachers' prior knowledge for teaching in an alternative certification program, J. Res. Sci. Teach., 46(4), 357–383.
  25. Friedrichsen P., van Driel J. H. and Abell S. K., (2011), Taking a closer look at science teaching orientations, Sci. Educ., 95(2), 358–376,  DOI:10.1002/sce.20428.
  26. Gess-Newsome J., (2015), A model of teacher professional knowledge and skill including PCK: results of the thinking from the PCK Summit, in Berry A., Friedrichsen P. and Loughran J. (ed.), Re-examining pedagogical content knowledge in science education, New York, NY: Routledge, pp. 28–42.
  27. Grossman P., (1990), The Making of a Teacher, New York: Teachers College Press.
  28. Henze I., van Driel J. H. and Verloop N., (2008), Development of experienced science teachers’ pedagogical content knowledge of models of the solar system and the universe, Int. J. Sci. Educ., 30, 1321–1342,  DOI:10.1080/09500690802187017.
  29. Jones M. G. and Carter G., (2007), Science teacher attitudes and beliefs, in Abell S. K. and Lederman N. G. (ed.), Handbook of research in science education, New York: Routledge, pp. 1067–1105.
  30. Kagan D. M., (1992), Professional growth among preservice and beginning teachers, Rev. Educ. Res., 62, 129–169.
  31. Kind V., (2009), Pedagogical content knowledge in science education: perspectives and potential for progress, Studies in Science Education, 45(2), 169–204.
  32. Kind V., (2016), Preservice science teachers’ science teaching orientations and beliefs about science, Sci. Educ., 100(1), 122–152.
  33. Lederman N. G., Abd-El-Khalick F., Bell R. L. and Schwartz R. S., (2002), Views of the nature of science questionnaire: toward valid and meaningful assessment of learners’ conceptions of the nature of science, J. Res. Sci. Teach., 39(6), 497–521,  DOI:10.1002/tea.10034.
  34. Lee E. and Luft J. A., (2008), Experienced secondary science teachers’ representation of pedagogical content knowledge, Int. J. Sci. Educ., 30(10), 1343–1363.
  35. Lincoln Y. S. and Guba E. G., (1985), Naturalistic inquiry, Beverly Hills, CA: Sage.
  36. Loughran J., Berry A. and Mulhall P., (2006), Understanding and developing science teachers' pedagogical content knowledge, Rotterdam, The Netherlands: Sense Publishers.
  37. Luft J. A. and Roehrig G. H., (2007), Capturing science teachers' epistemological beliefs: the development of the teacher beliefs interview, Electron. J. Sci. Educ., 11(2), 38–63. Retrieved from http://ejse.southwestern.edu/article/view/7794/5561.
  38. Magnusson S. J. and Palinesar A. S., (1995), The learning environment as a site of science education reform, Theory Pract., 34(1), 43–50.
  39. Magnusson S., Krajcik J. and Borko H., (1999), Nature, sources and development of pedagogical content knowledge for science teaching, in Gess-Newsome J. and Lederman N. G. (ed.), Examining pedagogical content knowledge: the construct and its implications for science education, Boston: Kluwer, pp. 95–132.
  40. Marks R., (1990), Pedagogical content knowledge: from a mathematical case to a modified conception, J. Teach. Educ., 41(3), 3–11.
  41. Mavhunga E. and Rollnick M., (2016), Teacher- or Learner-Centred? Science Teacher Beliefs Related to Topic Specific Pedagogical Content Knowledge: A South African Case Study, Res. Sci. Educ., 46(6), 831–855,  DOI:10.1007/s11165-015-9483-9.
  42. Ministry of National Education, (2013), Secondary 10th Grade Chemistry Curriculum, Ankara: National Ministry of Education Publications.
  43. Nargund-Joshi V., Park-Rogers M. A. and Akerson V., (2011), Exploring Indian secondary teachers’ orientation and practice for teaching science in an era of reform, J. Res. Sci. Teach., 48(6), 624–647.
  44. National Research Council, (1996), National Science Education Standards. Washington, DC: National Academies Press.
  45. Nespor J., (1987), The role of beliefs in the practice of teaching, J. Curric. Stud., 19, 317–328.
  46. Padilla K. and van Driel J., (2011), The relationships between PCK components: the case of quantum chemistry professors, Chem. Educ. Res. Pract., 12(3), 367–378.
  47. Pajares M. F., (1992), Teachers' beliefs and educational research: cleaning up a messy construct, Rev. Educ. Res., 62(3), 307–332.
  48. Park S. and Chen Y. C., (2012), Mapping out the integration of the components of pedagogical content knowledge (PCK): examples from high school biology classrooms, J. Res. Sci. Teach., 49, 922–941,  DOI:10.1002/tea.21022.
  49. Park S. and Oliver J. S., (2008), Revisiting the conceptualisation of pedagogical content knowledge (PCK): PCK as a conceptual tool to understand teachers as professionals, Res. Sci. Educ., 38(3), 261–284.
  50. Patton M. Q., (2002), Qualitative evaluation and research methods, 3rd edn, Thousand Oaks, CA: Sage.
  51. Roberts D. A., (1982), Developing the concept of ‘curriculum emphases’ in science education, Sci. Educ., 66(2), 243–260.
  52. Roberts D. A., (1988), What counts as science education? in Fensham P. (ed.), Development and Dilemmas in Science Education, London: The Falmer Press, pp. 27–54.
  53. Schneider R. M. and Plasman K., (2011), Science teacher learning progressions: a review of science teachers’ pedagogical content knowledge development, Rev. Educ. Res., 81(4), 530–565.
  54. Shulman L. S., (1986), Those who understand: knowledge growth in teaching, Educ. Res., 15, 4–14.
  55. Shulman L. S., (1987), Knowledge and teaching: foundations of the new reform, Harv. Educ. Rev., 57(1), 1–23.
  56. Tamir P., (1988), Subject matter and related pedagogical knowledge in teacher education, Teach. Teach. Educ., 4(2), 99–110.
  57. Tsai C. C., (2002), Nested epistemologies: science teachers' beliefs of teaching, learning and science, Int. J. Sci. Educ., 24(8), 771–783.
  58. van Driel J. H., Bulte A. M. and Verloop N., (2008), Using the curriculum emphasis concept to investigate teachers’ curricular beliefs in the context of educational reform, J. Curric. Stud., 40(1), 107–122.
  59. Veal W. R. and Kubasko D. S., (2003), Biology and geology teachers’ domain-specific pedagogical content knowledge of evolution, J. Curric. Superv., 18(4), 334–352.
  60. Volkmann M. J., Abell S. K. and Zgagacz M., (2005), The challenges of teaching physics to preservice elementary teachers: orientations of the professor, teaching assistant, and students, Sci. Educ., 89(5), 847–869.

Footnote

This study is a part of the first author's doctoral dissertation.

This journal is © The Royal Society of Chemistry 2020