Of teachers and textbooks: lower secondary teachers' perceived importance and use of chemistry textbook components

Abstract

According to research findings from all over the world, textbooks play an important role for teachers in the choice of methods, content and educational goals. However, the open textbook market, where the state's influence is limited, results in a significant gap between the state (written) curriculum and actual classroom practice. To understand this phenomenon in more detail, teachers’ (N = 387) conception of lower-secondary chemistry textbooks was evaluated, based on their perception and use of particular textbook components. Data obtained with an online questionnaire were subjected to a thorough analysis using CRISP-DM data mining methodology. The results showed a high consistency in chemistry teachers’ perception of textbooks and also that only a limited number of textbook components are frequently being used in teaching practice. The vast majority of teachers mentioned using textbook content to prepare lessons, which indicated textbooks’ influence over lesson content. The other most frequently used components are graphical representations, questions and tasks. Textbook components which can be used to apply a student-centred approach are considered less important by the majority of teachers, which confirms the persisting teacher-centred approach in chemistry teaching. The results also helped identify textbook components whose innovation could have the highest impact on education (educational illustrations, structured text, photographs and tasks). This study therefore sheds more light on chemistry teaching, as well as bringing important knowledge to new textbook authors. The data mining methodology proved useful in this sort of research, showing multiple relations which would not be considered in standard data analysis.

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Introduction

Recently, the fragility of education systems built on teacher-centred instruction was seen during the pandemic. The problems of a teacher-centred approach were widely exposed when students remained hidden behind their computers (e.g.Goncalves and Capucha, 2020; Hamamra et al., 2021). This situation invoked the need for structured, thematically separated, and complex teaching materials (cf.Murphy and Shelley, 2020; Spraakman, 2020; Moundy et al., 2021). The immense role of teachers, not only as the bearers of knowledge but also as enforcers of students’ learning, was revealed when, in many countries, education moved online. Parents experienced a typical school day as well as what it takes to teach their children.

Various material requests and spontaneous lesson tips literally flooded teachers’ groups on social media as well as journals (among others Holme, 2021; MDPI, 2021), despite textbooks seeming like an ideal tool under these circumstances. This fact could indicate teachers’ dissatisfaction with contemporary textbooks or their specific vision of textbooks’ potential use in education. With respect to contemporary knowledge about teachers’ attitudes to textbooks (Vojíř and Rusek, 2021a, 2021b), this could also be interpreted as teachers being satisfied with textbooks and using them for ordinary face-to-face instruction but not as a general tool, also usable in the online environment. If confirmed, this would mean textbooks only represent an ordered subject-matter set with additional supplementary ideas, suggested methods, and pictures for teachers to use to form their own teaching units, strongly based on their complete control of the situation. At the same time, this would signal to textbook authors that their effort to build comprehensive learning units was in vain. Nevertheless, teachers’ approach to using textbooks points to their conception of instruction and is therefore worth studying as it can provide information that can only be ascertained by lesson observations and interviews (Vojíř and Rusek, 2021a, 2021b).

Theoretical background

The textbook's role is different at each level of education and in each school subject, thanks to the field's specifics. All school subjects, however, are supposed to work in unison to achieve the educational objectives anchored in the curriculum. As pointed out by Remillard (2005), the use of the curriculum is influenced by the relationship between the teacher and the curriculum. For this reason, in order to understand the educational process from the curricular point of view, it is necessary to examine both the curriculum and the teachers’ approach, including their perception of and stance toward curriculum materials, such as textbooks (Remillard, 2005).

In general, textbooks are the most commonly used educational tool at lower-secondary level. They serve many functions such as: motivation, information, systematization, coordination, differentiation, guidance, learning strategy development, self-evaluation and education in a society's values (Mikk, 2000). Science (especially chemistry) textbooks, which this paper is focused on, also remain a very current topic as far as education research is concerned (Vojíř and Rusek, 2019).

Textbooks’ specific position among other teaching materials results from their relatedness to the curriculum. Their content serves as a translation of the intended curriculum for many teachers (Chiappetta and Fillman, 2007), and by structuring and presenting the core subject matter they also serve as the primary source for instruction (Mullis et al., 2012). Some authors even mention textbooks as the main information source to design lesson content (Johansson, 2006). In this respect then, textbooks represent a potentially implemented curriculum (Törnroos, 2005) and are reported to strongly influence teaching methods (Lepik et al., 2015). Textbooks were also found to provide teachers with additional materials, such as a more detailed description of the course, additional methodological suggestions or theoretical background knowledge (Steenbrugge et al., 2013). Therefore, it seems that state curricula are mediated by textbooks or could even be bypassed when textbooks differ from them. This phenomenon is strengthened if textbooks published before curricular reforms are considered consistent with the new curriculum and are further used by teachers (Vojíř and Rusek, 2020). The well-described curriculum time lag (Schoenbaum et al., 2015) affects the implemented curriculum long after it was officially changed. It is impossible to realize curricular changes without the ideas being integrated into the textbooks being used (see Mikk, 2000), which sometimes means having brand new textbooks published. In a commercial curriculum system (see Hemmi et al., 2013), institutions responsible for curriculum are required to cooperate with private publishers.

Research in the field of science textbooks has only partly been focused on the way textbooks are being used (see Vojíř and Rusek, 2019). Researchers focused on text-difficulty (e.g.Rusek et al., 2016; Rusek and Vojíř, 2019; Hu et al., 2021), visual representations (Gkitzia et al., 2011; Nyachwaya and Wood, 2014; Nyachwaya and Gillaspie, 2016; Chen et al., 2019; Lodge and Reiss, 2021), incorporating philosophical approaches (e.g.Aydin and Tortumlu, 2015; Phillips et al., 2015; Marniok and Reiners, 2016; Khaddoor et al., 2017) or analyses of various subject matter topics (e.g.Niaz and Costu, 2009; Osterlund et al., 2010; Bergqvist et al., 2013; Chang et al., 2020). However, there is only limited knowledge about the way textbooks affect real classroom practice. According to Stein et al. (2007), and in accordance with the above-mentioned Chiappetta and Fillman (2007) and Törnroos (2005) studies, teachers mostly prepare their lessons in line with the textbook(s) (Sikorová, 2010; Vojíř and Rusek, 2021a, 2021b) they use. The subject-matter and methods in observed lessons correlated with the textbook used (Bergqvist and Chang Rundgren, 2017). According to Harrison (2001), teachers also use models and examples or analogies from textbooks.

Several authors also investigated textbook tasks. The tasks often merely put emphasis on science content, not on science process skills (Coelho da Silva et al., 2019). Practical activities rarely engage students in authentic investigations (Kahveci, 2010), and scientific inquiry is present only implicitly (Andersen, 2020). The results, again, confirm a very similar conception for textbook task parameters. Bakken and Andersson-Bakken (2021) even speak of a certain genre that textbook tasks follow, which are open-ended questions mostly targeting facts, only simple contexts, no complex concepts (Ferreira and Saraiva, 2021) and a lack of opportunity to develop competences (Bakken and Andersson-Bakken, 2021).

The effect of textbooks on education (potential usability) depends on their structural components and the way they are being used by teachers, both in preparing their lessons and in the classroom. The latter was examined via lesson observations. In Červenková's (2010) research, text from textbooks was used in 81%, pictures were used in 25% and tasks in 72% of the lessons observed where textbooks were used. Sikorová (2010) found that in mathematics lessons, textbooks were used for new subject-matter processing for 44% of the lesson time (under 20 minutes) and a little under 40% to fix knowledge or practise. Almost 45% of all teachers in a study including teachers from Finland, Norway and Estonia reported using textbooks as an exercise book only during lessons (Lepik et al., 2015). This is in accordance with Sikorová's (2010) findings – that 55% teachers in her research reported using textbooks for practice.

In this research, the chemistry textbooks that teachers choose (Vojíř and Rusek, 2021a, 2021b) are considered an indicator of their teaching conception. Together with deeper analysis of a particular textbook's structural components (Rusek et al., 2020), the purpose of their selection and use brings information which helps understand chemistry education in more detail. As it is a textbook's structural components that carry the instruction to students, understanding teachers’ perceptions of their importance in the educational process and use shows teachers’ overall approach to curriculum implementation. The textbook components with the biggest proven impact, as well as the components whose effect can potentially be increased based on the ascertained information, can be identified and put into a centre for innovative endeavours when new textbooks are created t promote a new curriculum. At the same time, certain aspects of teacher training could be adjusted based on the research's results.

With respect to a textbook's role being the translation of the potentially implemented curriculum (Chiappetta and Fillman, 2007) or an example of the topics’ didactical transformation (see Shulman, 1986), several parallels were found in the way teachers choose textbooks in different countries. Similarities were found in selecting educational content (see Johansson, 2006; Lepik et al., 2015; Chou, 2021), using graphical components (cf.Bizzo et al., 2007; Shehab and BouJaoude, 2017) and considering tasks in textbooks (cf.Sikorová, 2010; Hundeland, 2011). A deeper understanding of each individual component's use on a national level seems to provide information on general validity and therefore bring necessary knowledge to textbook theory.

Research goals

How teachers use textbooks, more precisely the structural components they contain, can have a major impact on how the curriculum is implemented. Based on previous findings from the research focused on the use of different chemistry textbook series in Czechia and teachers’ attitudes towards textbooks as a whole (Vojíř and Rusek, 2021a, 2021b), research goals were established to map the ways chemistry textbooks’ structural components are perceived by teachers and how they are being used in lower-secondary schools. The goals are characterized by the following research questions (RQ) for the lower-secondary school environment:

(1) How important do teachers consider individual structural components of chemistry textbooks for the quality of chemistry education?

(2) How often do teachers use chemistry textbooks’ individual structural components and what factors influence them?

(3) For what purposes do teachers use individual structural components of chemistry textbooks and what factors influence them?

Finding out teachers’ perception of textbooks’ individual structural components and their use is important to assess the chemistry teaching conception at lower-secondary schools. To understand the typical teacher's approach, the perceived importance of textbook components, how often they were used and why were also considered in relation to the teachers’ characteristics (length of practice, subject specialization, perception of textbook importance for preparation, etc.). In this paper, a proven methodology is introduced to obtain teachers’ chemistry teaching conception profile based on their use and perception of a textbook's structural components.

Methods

Background of the study: chemistry textbooks in Czechia

At lower-secondary schools in Czechia, chemistry is taught in the last two grades (8th and 9th). The state provides all lower-secondary school students with textbooks. The textbook chosen by the school respective, more commonly, teachers, i.e. the curriculum is fully commercial. In 2020, there were 12 different chemistry textbook sets in use (Vojíř and Rusek, 2021a, 2021b). However, only four of these are being used in 95% of schools. Later in the text, these textbooks are referred to using the following abbreviations – see Table 1.

Table 1 The list of referenced textbooks

Textbooks	Proportion of schools^a (%)	Abbreviation
a According to Vojíř and Rusek, (2021a, 2021b).
Základy chemie 1 (Beneš et al., 1993a, 1993b)	28	ZCH
Základy chemie 2 (Beneš et al., 1993a, 1993b)
Základy praktické chemie 1 (Beneš et al., 1999)	16	PCH
Základy praktické chemie 2 (Beneš et al., 2000)
Chemie pro 8. ročník (Mach et al., 2016)	38	NS
Chemie pro 9. Ročník (Šibor et al., 2015)
Chemie 8 (Škoda and Doulík, 2006)	20	Fr
Chemie 9 (Škoda and Doulík, 2007)

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With respect to the year of publishing, the ZCH and PCH textbooks are considered to represent the curricula from the early 1990s. The NS and Fr textbooks were published about 10 years after the last curricular reform and were therefore the newest, state approved, textbooks on the market at the time the research was conducted (Vojíř and Rusek, 2020). A closer look at the NS textbook structure shows that they, nevertheless, follow the traditional chemistry curriculum (cf.Johnstone, 2010) but in a more modern manner, supported by photographs. The only exception is the Fr books, whose authors experimented with the traditional subject matter order, considering carbohydrates hydrides and, therefore, placing them in the 8th instead of the traditional 9th grade textbook in the organic chemistry. Also, abstract and mostly unpopular topics such as chemistry calculations (cf.Rusek et al., 2021; Rusek et al., in press) were placed at the beginning of the 9th grade book. A new Fr edition with a more traditional subject matter order is currently available but was not yet on the market at the time of the research. Apart from the structure, however, these textbooks are analogous and contain the same didactical components (Rusek et al., 2020). This finding showed an inclination towards a traditionally conceived curriculum, which was later confirmed by another study which revealed teachers were satisfied with traditional textbook styles originating in the 1990s (Vojíř and Rusek, 2021a, 2021b). In addition, all commonly used chemistry textbooks for lower-secondary schools are didactically well-equipped, i.e. they contain a wide range of structural components for various uses in education (Rusek et al., 2020). However, the use of individual components has not yet received any attention.

Research tool

This research used quantitative methods. An online questionnaire was used. Its validity and reliability had been tested beforehand (Vojíř and Rusek, 2019). It mainly consisted of closed-ended questions under the following categories: respondent characteristics, textbooks used by students and by teachers as preparation for teaching, textbook choice, teacher textbook satisfaction, perceived textbook importance for lesson preparation, how often and how the textbook's didactical equipment is used in education. In the questions on textbooks used, ‘Other’ answer was possible.

15 structural components for textbooks were assessed, taken from Průcha (1989): plain text (expository text in continuous paragraphs); structured text (expository text structured in overview diagrams, tables, etc.); subject-matter summary; supplementary texts (documentation material, references, statistical tables, etc.); explanatory notes; vocabulary of scientific terms (with explanation); educational illustrations (schematic drawings, models, etc.); photographs; graphs and diagrams; learning tasks; complex tasks instruction (instructions for experiments, laboratory work, etc.); out-of-school topics; explicit goal setting (for students); self-evaluation tools (for students); references to other sources. Frequency of component use and their perceived importance in the quality of chemistry education were assessed using five-point Likert scales (1 – I use very often (practically in every lesson/its preparation) up to 5 – not using; 1 – very important to 5 – completely unimportant) where only the limiting points (1, 5) were verbalized. Cronbach's alpha was used to assess the reliability of these scales: the frequency of use scale was α = 0.870, perceived importance was α = 0.899. Both values suggest acceptable reliability (Tavakol and Dennick, 2011). The way individual structural components in the textbooks are used was examined using closed-ended question with options: preparation for teaching, realization of teaching, student homework, and expanding activities for individual students.

Research sample

The sample for this study was based on the total number of lower-secondary schools in Czechia in 2017/2018 (MŠMT, 2018). A minimum sample (95% confidence level) was calculated using the Raosoft minimum sample calculator (https://www.rasoft.com). As it is impossible to differentiate between full basic schools (schools which offer all grades of elementary and lower-secondary education) in the address list, the minimum sample was multiplied by the proportion of lower-secondary schools where chemistry is being taught. The sample was extended due to the expected online survey response-rate (cf.Nulty, 2008).

The schools were randomly chosen from the Czech Ministry of Education's school address book (MŠMT, 2018). Next, 1536 schools were addressed via an email sent to the schools’ headmasters. They received an explanation of the research's purpose, instructions, and a link to the online questionnaire.

The data were collected from September to November 2018. In total, 387 teachers from 370 schools filled in the questionnaire. The response-rate calculated after the schools with no chemistry education were excluded from the sample was 41%. As the number of participating schools exceeded the minimum sample and were selected randomly, the findings are generalizable to all lower-secondary chemistry teachers in Czechia.

Data analysis

The data gathered using Likert-scales were considered ordinal. To compare selected teacher groups, medians were used. To discover interesting relationships between variables in the dataset, association rule learning (Piatetsky-Shapiro, 1991) was used. In the descriptive rule discovery process, a series of tasks were set to find all rules fulfilling predefined statistical measures. The regularities in the data can be expressed in the form of IF-THEN rules (antecedent ⇒ consequent) (Fürnkranz and Kliegr, 2015).

CRISP-DM methodology (Chapman et al., 2000) was used in this procedure, and is widely used in the business and medical research fields. However, it has already been used in education-oriented research too (e.g.Vialardi et al., 2011; Oreski et al., 2017).

In the data preparation process (see Fig. 1), other textbooks the respondents declared using were coded and added analogically to the closed-ended questions. The multiple-choice items were separated into individual attributes with a dichotomic value. For the first round of data rule mining, the original five-point scales were converted to 3-point scales by merging values 1 and 2 as a positive and 4 and 5 as a negative attitude. For further analysis, all items from the questionnaire prepared in this way were used (N = 137). The EasyMiner system was used to finalize data pre-processing into attributes and data mining in the modelling phase (see Fig. 1). This system uses data mining operations based on the R framework (Vojíř et al., 2018).

Fig. 1 The data mining process diagram.

To select interesting rules from the mining, confidence, support and lift constraints were used. A rule's confidence (c) is defined as c(X ⇒ Y) = s(X ∪ Y)/s(X). Confidence is thus an indication of the rule's frequency of truth, which is therefore an indicator of the rule's reliability. The support (s) for an X itemset is defined as the proportion of X values in the dataset which contain the itemset. The s(X ⇒ Y) is therefore possible to be interpreted as the probability of a synchronous X and Y itemset's appearance in one implication relation. The lift (l) is defined as l(X ⇒ Y) = s(X ∪ Y)/(s(X)s(Y), which shows the support of the whole rule (see Hahsler et al., 2005). If lift is greater than 1, it shows above average performance of the associated rule. A higher value corresponds with a more strongly occurring interdependence within the population as a whole (cf.Rauch and Šimůnek, 2014).

In the first mining step, a task was typically set to: confidence minimum value: 0.7, support minimum value: 0.05 and lift minimum value: 1.1. The rules were explored in all of the 137 questionnaire items. In each of the CRISP-DM cycles, the itemsets and levels of constraints were repeatedly changed in order to receive rules of higher interest concerning the potential impacts on educational reality. With the focus of this research in mind, rules valid for most teachers (confidence above 0.5 and lift above 1) were explored. To find generally valid, non-blending rules to interpret, the maximum rule length was set to three items. The mined data-rules’ were then evaluated (see Fig. 1) by two science education researchers in the context of the research questions.

For clarity's sake, interesting rules that were mined are presented in the verbal form of the if-then variable relation. The validity of the presented mined rules is expressed by the confidence, support and lift values in brackets after the verbal formulation of each rule.

Research results

Importance of textbook structural components for chemistry education quality (RQ1)

In light of the teachers’ opinion on textbooks and their use described above, their perception of a particular textbook's structural components offers further information on the intended and implemented chemistry curriculum. Teachers’ perceived importance of components for quality chemistry education differs significantly. Nevertheless, the teachers did not consider any of the components insignificant, so no direct suggestions to re-evaluate textbook structure was found.

More than half of the teachers considered eight of the components important for chemistry education (see Fig. 2). The following components were indicated as the most important (Med = 2) for teachers. Therefore, they represent a fundamental textbook structure: structured text, educational illustrations and subject-matter summary. By contrast, the least important (however still considered neutral – Med = 3) were the following textbook components: vocabulary for scientific terms, explicit goal setting for students, and references to other sources of information.

Fig. 2 Perceived importance of components in textbooks.

In the teachers’ perception of components in relation to a specific textbook, only partial differences were found for the most commonly used textbook, NS. Teachers who could choose the textbook themselves and use the NS textbook typically consider the following components very important (Med = 1): structured text, plain text, educational illustrations, subject-matter summary, photographs, Learning tasks, and graphs and diagrams.

Frequency of the use of textbook structural components (RQ2)

To find out the purpose the textbooks are being used for, the teachers answered questions about the frequency of a particular textbook's component use (1–5 scale: use very often – never use). The results showed the most frequently used components are: structured text, photographs, and educational illustrations. Based on the medians of teacher answers (Med = 2), their use can be considered frequent. On the contrary, the topics for out of classroom activities, explicit goal formulation for students, and references to other sources of information are the least frequently used (Med = 4). The variability in the answers suggest teachers use them sometimes to rarely (Fig. 3).

Fig. 3 Frequency of use of components in textbooks.

Although more than half of the teachers consider eight textbook components important (i.e. are expected to be included in textbooks), only four components were mentioned as being used frequently by the majority of teachers (cf.Fig. 2 and 3).

Relationships between frequently used structural components for textbooks. An outstanding cohesion was found in teachers’ use of graphical components. The teachers who use educational illustrations often also tend to make frequent use of textbook photographs (c = 0.773, s = 0.581, l = 1.226) and/or graphs and diagrams (c = 0.529, s = 0.398, l = 1.249). Very high-lifted correlations apply to how frequently these components are used, and also vice versa: the majority of teachers who use educational illustrations seldom, also seldom use photographs (c = 0.8, s = 0.052, l = 6.45) and/or graphs and diagrams (c = 0.84, s = 0.054, l = 3.653).

A similar relationship with was found with high confidence among textual components. The teachers who do not tend to use structured text typically also seldom use plain text (c = 0.8, s = 0.093, l = 2.517), subject-matter summary (c = 0.733, s = 0.085, l = 2.677), explanatory notes (c = 0.711, s = 0.083, l = 1.448), and goals (c = 0.733, s = 0.085, l = 1.594).

Other positive trends were found across the most commonly used components. The frequent use of structural components often overlaps, which points to a pattern between textbook use and teacher's teaching conception. The teachers using structured text are often also likely to use educational illustrations (c = 0.855, s = 0.517, l = 1.137) or photographs (c = 0.709, s = 0.429, l = 1.125).

Several factors influencing the frequency of a textbook's structural component use was identified. These were mainly the textbook in use, the characteristics of teachers and their perception of the textbooks they use and the importance of particular textbook components for the quality of chemistry education.

Structural components’ frequency of use with respect to the textbook in use. Regarding specific textbook sets, significant relationships were found between graphical material in the newest textbooks on the market at the time of the research period – NS and to some extent, Fr. These textbooks include photographs in good resolution and depict objects students are familiar with (for example cars, phones, etc.). More than 83% of the teachers who want to acquire an NS textbook set reported often using educational illustrations (s = 0.065, l = 1.108). This corresponds with the trend among teachers already using NS textbooks. Among these, the use of educational illustrations is significantly more frequent (c = 0.833, s = 0.318, 1.105).

The second highest proportion of teachers who use educational illustrations often was found among Fr users (c = 0.753, s = 0.15, l = 1.002). Also, almost 72% of teachers mentioned they often use photographs from the NS chemistry textbook (s = 0.274, l = 1.136).

Role of teacher characteristics and their perception of textbooks in the frequency of structural component use. The data analysis showed strong correlation between particular textbook's component use and perceived textbook importance for lesson preparation. The majority of teachers who consider textbooks important for lesson preparation reported they often use: plain text (c = 0.538, s = 0.256, l = 1.487), structured text (c = 0.761, s = 0.362, l = 1.258), subject-matter summary (c = 0.592, s = 0.282, l = 1.239), graphs and diagrams (c = 0.505, s = 0.24, l = 1.193), complex tasks instruction (c = 0.511, s = 0.243, l = 1.156), learning tasks (c = 0.668, s = 0.318, l = 1.13), photographs (c = 0.712, s = 0.339, l = 1.129), and educational illustrations (c = 0.832, s = 0.395, l = 1.106). The lift of these relationships points to the teachers’ overall perception of textbooks – learning content delimitation.

Teachers who consider textbooks unimportant for their lesson preparation typically seldom use plain texts (c = 0.714, s = 0.078, l = 2.247). A large proportion of teachers with the longest teaching practice, who consider textbooks unimportant to prepare for their lessons, seldom use structured text (c = 0.767, s = 0.059, l = 2.412) or explanatory notes (c = 0.7, s = 0.054, l = 1.426). The results suggested that more experienced teachers are likely to use the text less often than their novice colleagues. The proportion of teachers who use structured text decreases with their length of practice. In the group of teachers with more than 10 years’ experience, the proportion of teachers using plain text often is considerably lower (c = 0.33, s = 0.243, l = 0.912) than novice teachers with less than 1 year experience (c = 0.66, s = 0.21, l = 1.701).

On the contrary, no significant differences in the use of graphic components were found regarding the length of practice. Graphic components are also used by teachers of all specializations. Even the teachers who also teach information and communication technology tend to use photographs from textbooks often in more cases than the other teachers (c = 0.746, s = 0.129, l = 1.184).

Apart from the text and graphical components, teachers’ textbook perception also significantly affects the use of Learning tasks. Almost 74% of the teachers who reported that textbooks are important for their lesson preparation often use Learning tasks from the textbook if they are satisfied with the textbook in use (s = 0.266, l = 1.243). The Learning tasks are also often used by a higher proportion of more experienced teachers (10 and more years of practice) who consider the textbook important for their lesson preparation (c = 0.708, s = 0.238, l = 1.196). This finding is surprising as more experienced teachers were expected to rely on external resources less. This further increases the importance of textbooks, which seem not to serve teachers only at the beginning of their career.

Frequent Q&T use is most associated with ZCH and NS textbook set users. Accordingly, the teachers who consider textbooks useful for lesson preparation often use Learning tasks (ZCH: c = 0.724, s = 0.163, l = 1.286; NS: c = 0.724, s = 0.163, l = 1.224). These textbooks then seem to be a source of student-activating components for these teachers. More than 71% of ZCH textbook users who are satisfied with this book often use Learning tasks (s = 0.096, l = 1.202).

Last but not least, another relationship was found between the textbook's structural components directly aimed at students’ active learning. The teachers who use Learning tasks are also likely to use educational illustrations (c = 0.838, s = 0.496, l = 1.115), or photographs (c = 0.716, s = 0.424, l = 1.136).

Relationship between perceived importance and frequency of structural component use. Strong dependences were found between teachers’ perceived unimportance of components and their actual use. Teachers tend to use components they consider less important for quality of education only rarely (see Fig. 4).

Fig. 4 Medians of perceived importance and frequency of use of components in textbooks.

For instance, the strongest correlation between perceived low component importance and its rare use was found for: subject-matter summary (c = 0.88, s = 0.054, l = 3.195), instructions for complex tasks (c = 0.767, s = 0.059, l = 3.297), structured text (c = 0.91, s = 0.08, l = 2.869) and photographs (c = 0.714, s = 0.052, l = 5.759).

If teachers consider a certain component important for the quality of education, they typically use it very often. These relations are valid for most teachers. The most above-average relations were found for: supplementary texts (c = 0.515, s = 0.225, l = 1.607), graphs and diagrams (c = 0.655, s = 0.372, l = 1.545) or complex tasks instructions (c = 582, s = 0.395, l = 1.317).

Purpose of the textbook's structural component use (RQ3)

Considerable differences were found in the purpose for which teachers use the various structural components in a textbook (see Fig. 5). Most teachers reported using several textbook components during lessons. Overall, most teachers use 10 out of 15 textbook components for this purpose (see Fig. 5). The most frequently used are educational illustrations (82% of teachers), structured text (77%) and photographs (77%).

Fig. 5 Proportion of teachers using components in textbooks for specific purposes.

For students’ home preparation purposes, Learning tasks (44%), subject-matter summary (37%), or out-of-school topics (35%) are the most-frequently used components. To support extended activities, supplementary texts play a major role. Out-of-school topics (32%), vocabulary of scientific terms (30%) or Learning tasks (30%) are also used quite frequently, according to the responses.

As far as the use of textbooks for teachers’ lesson preparation is concerned, plain text dominates (used by 58% of teachers). This is in contrast to all the other textbook components observed. To prepare for education, a large group of teachers also use instructions for complex tasks (34%), and educational illustrations (29%).

As suggested above, a deeper understanding of the purpose for using the individual structural components provides information about their impact on education. For this reason, relationships with other aspects of textbook use were sought.

Relationship between the purpose and use of textbook structural components. When analysing teachers’ use of the textbook components for particular purposes, several relationships among the different textbook series were found (PCH, Fr and NS):

• An above-average proportion of teachers who use the PCH textbook use Learning tasks for home preparation purposes (c = 0.516, s = 0.085, l = 1.181), supplementary text as an extending activity (c = 0.578, s = 0.096, l = 1.196), and graphs and diagrams for lesson realization (c = 0.656, s = 0.109, l = 1.081).

• An above-average proportion of teachers who use the PCH textbook use plain text (c = 0.558, s = 0.111, l = 1.086) and the subject-matter summary for lesson realization (c = 0.636, s = 0.127, l = 1.095).

• An above-average proportion of teachers who use the NS textbook use complex tasks (c = 534, s = 0.204, l = 1.059), plain text (c = 0.554, s = 0.212, l = 1.077), Learning tasks (c = 0.689, s = 0.264, l = 1.102), structured text (c = 0.818, s = 0.313, l = 1.058), and educational illustrations in lesson realization (c = 0.865, s = 0.331, l = 1.056).

Despite the differences found in the purposes for using particular textbook components, lower lift values for these rules suggest that there are only partial differences.

Relationship between the purpose and frequency of the textbook's structural component use. The highest lift was found for the relationship between several often-used components and purpose for lesson preparation. This mainly concerns photographs (c = 0.312, s = 0.199, l = 1.34), Learning tasks (c = 0.358, s = 0.214, l = 1.319), structured text (c = 0.312, s = 0.191, l = 1.185), and educational illustrations (c = 0.34, s = 0.258, l = 1.145). If teachers use these components often, a significantly higher proportion of them use these components to prepare their lessons. Similar trends were found for the relationship between the perceived importance for the quality of education and purpose of a component's use. These similarities concern: graphs and diagrams (c = 0.277, s = 0.160, l = 1.428), Learning tasks (c = 0.331, s = 0.240, l = 1.220), complex task instructions (c = 0.415, s = 0.284, l = 1.199) and the subject-matter summary (c = 0.228, s = 0.178, l = 1.195). The only exception to this trend is plain text. This component is most used for lesson preparation and when teachers use it frequently, they are also more likely to use it for lesson realization (c = 0.62, s = 0.401, l = 1.2).

The influence of teachers’ characteristic on the purpose of using the textbook's structural components. Most above-average dependencies were found for freshman teachers, but the support for these relationships is considerably low as the group was smaller. A higher number of these teachers use supplementary texts (c = 0.538, s = 0.018, l = 1.667) educational illustrations (c = 0.923, s = 0.031, l = 1.123) or Learning tasks (c = 0.692, s = 0.023, l = 1.103) for lesson realization. They also demonstrated above-average use of 12 out of 15 evaluated textbook components to prepare lessons.

With the exception of textual components, no significant trends were found in teachers’ use of textbook components in relation to their length of practice. In most cases, the way components are used remains more or less constant. As far as plain text is concerned, the highest proportion of teachers using this component for lesson preparation was found in the teachers with 1–3 years of practice (c = 0.852, s = 0.059, l = 1.465). High lift values were also found for freshman teachers.

Discussion

The research results provide a comprehensive insight into chemistry teachers’ perception of textbooks and their particular component use. With many parallels found between textbooks and teachers using textbooks worldwide (see Introduction), these results have the potential to inform researchers, textbook authors, teacher trainers and policy makers internationally.

Chemistry teachers hold a rather homogenous view of the textbook

Teachers pointed out eight most important components for the quality of chemistry education. Structured text, educational illustrations and a subject-matter summary were considered the most important by the vast majority of teachers in the sample. This confirms the highly homogeneous teachers’ view of chemistry textbooks as far as their components are concerned. From this point of view, the textbook set by NS (the most commonly used textbook (Vojíř and Rusek, 2021a, 2021b), with a modern design and traditional chemistry teaching conception) seems to best fulfil the teachers’ expectations. The perceived importance of the above-listed components (with the exception of graphs and diagrams) for education was confirmed by the NS users’ satisfaction with this textbook. More than 50% of the teachers who provide their students with the NS textbook are completely satisfied with it if they consider the seven above-listed components very important for the quality of chemistry education. This finding then points to the textbook authors’ successful attempt to write a textbook for a specific target group.

Textbook components are not used equally

The textbook or textbook components’ impact on education is a product of how frequently the textbook is used in education together with the length of their use within lessons (cf.Janík et al., 2007). Although teachers reported several textbook components as important, the majority of teachers frequently use only some of them. The discrepancy between the perceived importance and use of the components is surprising. This finding could be explained by the teachers’ beliefs about the purpose and use of textbooks (see Bergqvist and Chang Rundgren, 2017) as well as a certain image of the typical textbook shape they have learnt to respect.

Most teachers use educational illustrations, structured text and photographs, i.e. components which mostly support the frontal, teacher-centred approach. Components aimed at individualization, such as explicit goal setting, self-evaluation or vocabulary/notes & explanations are used only seldom. This, again, points to the teachers’ traditional teaching conception. In this way, many important competencies seem not to be developed.

Teachers did not express their wish to use another textbook (57% of the teachers mentioned they do not want another one of the contemporary textbooks available and 23% do not know what other textbook they would like) and also seemed to be satisfied with the textbook they use (Med = 2 on the 5-point scale) (Vojíř and Rusek, 2021a, 2021b). This suggests the contemporary shape of textbooks suits their chemistry teaching conception. Yet, (1) they seem not to use the components fully and (2) analysing the component revealed considerable reserves in components’ quality and also placement in the books (e.g.Rusek and Vojíř, 2019; Vojíř, 2021; Vojíř and Rusek, 2022).

Teachers need to trust textbook component quality before they employ them in their teaching

The results showed teachers use components they consider most important more often. Therefore, the educational reality cannot be changed by simply changing the written, intended curriculum, including textbooks (cf.Bergqvist and Bergqvist, 2017). It is possible to change the quality and potential of individual textbook components, however, unless teachers consider these improved components important, they are unlikely to use them. It is therefore also necessary to focus on changing the concept of teaching supported by innovated textbook components, explain the background and reasoning behind the changes (Bergqvist and Bergqvist, 2017) and provide further supporting training. As teachers are known to over-scaffold their students when they encounter a complex task (Son and Kim, 2015), any significant changes would either remain unused by the teachers or would only be altered to suit their original conception of teaching.

The frequency of graphical component use is especially related to the textbook in use

Teachers are provided a list of textbooks to choose from which are approved by the Ministry of Education (see Vojíř and Rusek, 2020) and are expected to choose a book which suits them best. This suggests they are expected to acquaint themselves with the textbooks, i.e. their overall appearance, conception and the structural component quality. However, differences in specific textbooks’ particular components seem not to be a decisive factor in the frequency of their use. The exceptions to this are only the graphical components, which seem to play a specific role in teacher preferences (cf.Bizzo et al., 2007). Czech chemistry textbooks’ long lifespan has been shown to be ineffective by this research. With the constant need to bring science phenomena closer to students, visualizations at all levels of representation are needed (Talanquer, 2011; Taber, 2013). The finding that teachers using newer textbooks use their graphical components more points to the limitations of older textbooks with less vivid, even outdated graphics.

Surprisingly, a textbook's graphical material plays an important role, although there is an increasing quantity of free online resources. This may be due to teachers’ trust in the textbook authors to choose appropriate representations. At the same time, the field of a teacher's degree does not seem to have an effect. On the contrary, teachers qualified for teaching chemistry and ICT – who were expected to exploit vast online resources the most (Rusek et al., 2017) – use textbook graphical components more than teachers from other field combinations.

The use of textbook tasks depends on how important the textbook is perceived to be for lesson preparation

This finding is in accordance with Bergqvist and Chang Rundgren, (2017), who discovered a link between teachers’ teaching conception and textbook use. With respect to recent findings (Vojíř and Rusek, 2022), persisting textbook task genre very probably represents another, considerable hurdle for change. Considering how teachers draw inspiration from textbooks, they ask only a certain type of question, mostly only after their transmissive part of teaching. This is supported by the findings from this research. Using tasks was found to affect teachers’ use of the textbook for lesson preparation (and vice versa) or their satisfaction with the textbook. These results also raise questions as to whether the differences between particular textbooks’ Learning tasks use were caused by task quality or teacher expectations, and their conception of teaching (i.e. either purely transmissive or student-centred – task-supported conception). As found in the qualitative task analysis in the analysed textbooks (Vojíř and Rusek, 2022), they include tasks aimed primarily at fixing acquired educational content – a trend also known e.g. from Portugal (Coelho da Silva et al., 2019; Ferreira and Saraiva, 2021). Regarding teachers’ tendency to consider textbook content an example of the implemented curriculum, this shows a contrast with the curricula's intellectual demands, which target higher-order cognitive operations (Elmas et al., 2020; Kácovský et al., 2021). Future editions of existing textbooks or new materials need to be designed to take this issue into account (cf.Chinn and Malhotra, 2002).

Plain text is important for teacher preparation

With the exception of plain text, the largest proportion of teachers use all components to realize lessons. Based on the results, it seems that textual components (e.g.Rusek et al., 2016; Rusek and Vojíř, 2019), non-textual components (e.g.Zupanc and Devetak, 2021) and tasks (e.g.Bakken and Andersson-Bakken, 2021; Vojíř, 2021) could be considered the most important research topics in this field. These components can have the greatest impact on education. However, contemporary research has not yet covered them satisfactorily (see Vojíř and Rusek, 2019). In particular, the visual support that chemistry textbooks provide for meaningful chemistry learning remains considerably underexplored.

Only the plain text – the main component of contemporary textbooks – is used more by teachers for their own preparation than for realizing the lesson. The conclusions from textbook-text readability measurements – the majority of textbook text exceeds the recommended text difficulty (e.g.Rusek et al., 2016; Rusek and Vojíř, 2019) and may need to be reconsidered since the major recipients are, oddly enough, not students but their teachers – who can manage the text just fine.

The purpose of a component's use does not change with the length of the teacher's practice

There was a higher proportion of freshman teachers found using textbook components in lesson realization. They also seem to rely on textbooks more than their more experienced colleagues and use a larger proportion of textbook components for lesson preparation. This suggests teachers seek more support in terms of subject-matter content and presentations at the beginning of their career (cf.Bakken, 2019), which is probably due to them being less prepared for teaching practice. It also shows how the curriculum can be overshadowed by textbooks. However, it was found that teachers’ use of textbooks – i.e. utilizing their components – remains relatively constant during their years of practice. Although teachers' dependence on the textbook decreases slightly over time, the way the individual components are used does not change. This shows the need for specific support for freshmen teachers, although most cannot choose a textbook themselves (Vojíř and Rusek, 2021a, 2021b) and are in this sense influenced by their more experienced colleagues.

Challenges for curriculum changes

The textbook's specific role as an aid to serve teachers (Stein et al., 2007; Sikorová, 2010) was also confirmed in this research. As textbooks are intended primarily for students, this finding raises several questions. On one hand, teachers mentioned the need to use supporting material, however, most do not tend to use a teachers’ book (Vojíř and Rusek, 2021a, 2021b). Instead, they tend to pick some pieces which probably apply to their teaching conception, leaving the whole idea of the textbook's units/chapters behind. Once instructed to work with the textbook themselves, students probably experience only components pre-selected by the teacher. In such a manner, textbook authors’ ideas are likely to remain unheard. Teachers’ textbook evaluation then, rather than evaluating a teaching aid, represents how usable they find particular components, preferably without changing their teaching conception.

This conflict of purpose is problematic for several reasons:

(1) Materials for teachers and students logically differ in their nature. Authors of these tools need to take into account the different goals and adjust the language as well as the structure for either of the target groups.

(2) With teachers having a rather reserved attitude towards teacher's books, there are not many ways to deliver the textbook authors’ teaching ideas. Textbooks are clearly not the ideal platform, despite having obviously taken this role.

(3) Considering teachers do little work with the curriculum and textbook use is overstressed in this sense, changing textbooks is a crucial step in any significant curricular reform. However, based on the findings, only changes in subject-matter (new findings, clarifications, etc.) and new graphics have a direct way into the teaching process. Other vital parts such as the very philosophy of (chemistry) education, intended curriculum goals (see e.g.Khaddoor et al., 2017), underlying concepts (such as Nature of Science), student-centred approach, responsive teaching, and meaningful tasks are not likely to find their way into classrooms as the explanation of their purpose will remain unread in the teacher's books or in the (almost) unused textbook components. The only possible way out of this vicious circle seems to be a state-supported promotion and explanation of the curriculum change together with a vivid presentation of particular activities leading to the reformed goals. Once teachers see the goals are reasonable and can be reached with the use of the textbook components, teachers might be more likely to use them as intended, and a link between curriculum, textbook and classroom practice can be established.

Limitations

The impact of the results is mainly limited by the typical disadvantages of a questionnaire survey. However, the sample size and selection were performed in such a manner which allows the Czech teacher population to be generalized. Also, since the questions mostly targeted opinions on textbook components and asked for teachers’ experience, the chances for teachers to introduce bias were limited.

Lesson observations would surely provide more information on textbook use. Nevertheless, this approach would be more difficulty, especially with sample size and selection. It would also need to be completed with teacher interviews, which could include similar limits to the original questionnaire – teacher subjectivity and their endeavour to report an improved version of reality.

One of the key factors to reduce the limitations was using the data mining methodology. It enabled the investigation of a hypothesis which would not have initially been created by the researchers, and thus provided more information about the relationships in the system.

Conclusions

In this study, a representative sample of lower-secondary school chemistry teachers was asked to indicate the textbook(s) they use, their satisfaction with them, and the way they were chosen at their school. Special attention was given to specific textbook components that teachers use, together with their purpose of use. A significant homogeneity was found in chemistry teachers’ teaching attitudes – they lean towards a teacher-centred approach and favour traditional chemistry teaching conception.

Textbooks play a significant role in teachers’ lesson preparation and although teachers did not mark any of the textbook components as unimportant, students encounter only some components in chemistry lessons.

Teachers considered eight textbook components to be important for chemistry education quality. From these, the most frequently used components (with the highest impact on education) are: graphical components, structured text and tasks. Innovations focusing on these components therefore seem to have the biggest potential to influence teaching practice when new textbooks are released.

Plain text is used by most teachers for lesson preparation, structured text and visual components are typically used in lessons. This showed that the (chemistry) lesson content is significantly determined by the textbooks, which in many ways bypass the curriculum. Despite having a textbook, it seems that students typically receive the information processed by their teacher during the lesson's exposition phase. The textbook seems to be an aid to illustrate the teacher's instruction.

The graphical side proved to be a factor for teachers who consider textbook illustration important. Either they require a newer textbook or, once they have it, use illustrations more. Tasks were found to be a component often used for various purposes: lesson preparation, lesson realization, extension activities and students’ home preparation. In line with other research in the field, textbook tasks were identified as another component which needs special research attention.

Moreover, the results showed teachers consider textbook components focused on students (i.e. goal setting, self-evaluation tools, scientific vocabulary terms or links to other sources of information) to be the least important components for the quality of chemistry education (although not unimportant). These components are also used by a significantly smaller number of chemistry teachers. The effect of implementing student-oriented components into new textbooks therefore seems limited.

The results suggest mere textbook innovation would not have the intended effect and systematic teacher development focused on the skills necessary for their work with the learning materials seems desirable. Partial innovations in chemistry education can be supported by educational materials, especially in the subject matter's content, mainly by editing the explanatory text, visual components, and tasks. Including other activating components in the textbooks may not work as these are not the parts most teachers build their lessons on. Major reform targeting student competencies and (science) literacy development require new textbooks developed from scratch (not by updating older textbooks) and connected with teacher education (both pre- and in-service). An explanation of the textbook's philosophy also seems to be necessary, probably together with examples of their effect, due to the surprisingly almost unanimous current chemistry teaching paradigm.

Conflicts of interest

There are no conflicts to declare.

Acknowledgements

This publication was supported by the Institutional Support for Long-term Development of Research Organizations – Cooperatio HUM – Charles University, Faculty of Education (2022) and UNCE/HUM/024.

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