Personal journeys of teachers: an investigation of the development of teacher professional knowledge and skill by expert tertiary chemistry teachers

Abstract

Several common characteristics of the journey towards tertiary teaching expertise have been deduced through a detailed analysis of transcripts that originated from interviews conducted with ten recognised excellent tertiary chemistry teachers. The interviews were structured around Loughran's CoRe questions and yielded deep insights into the topic specific professional knowledge and reflective practice of the participants. The interview participants offered their insights into changes that occurred in their teaching strategies and practices as they progressed in their expertise. They also reflected on changes that they undertook over time within their teaching contexts in terms of engaging students and assessment, and what advice they wish that they had been given as new tertiary teachers. We have identified signposts of expert teacher professional knowledge and skill that further expand on our previously published outcomes including: seeking immediate feedback from students; a tendency to reduce total content to a critical minimum; reflective practice; and a willingness and ability to modify teaching approaches. The outcomes support our previous findings that tertiary chemistry teachers had primarily developed their PCK through their own teaching experiences and awareness of their own students’ outcomes, filtered by their individual beliefs and backgrounds. In this study, we provide new insight into the nature of inherent reflective practice that has evolved by experience rather than through formal professional development.

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Introduction

Tertiary teachers typically experience very different journeys in their development of professional practice and skills in comparison to primary and secondary teachers. For many, teaching is initially not a deliberate choice but has been embarked upon as an inherent part of their academic role, while for others teaching becomes something that they engage in with passion, and many engage in a scholarly approach to their teaching practice.

Much has been written about what expert teaching looks like at the secondary level (Loughran, 2010), ways to improve the preparation of pre-service teachers (van Driel et al., 2002; Kind, 2009a, 2014, 2017) and professional development of teachers (Supovitz and Turner, 2000; van Driel and Berry, 2012; Mocerino et al., 2015; Herrington and Daubenmire, 2016) using the lens of pedagogical content knowledge (PCK) to explore their topic-specific practice (Mavhunga, 2018). Recently, a sophisticated consensus model of teacher professional knowledge and skill (TPK&S) that encompasses PCK has arisen out of the characterisation of many aspects of the knowledge bases and professional knowledge that inform teachers’ classroom practice and ultimately, student outcomes (Gess-Newsome, 2015). This model was constructed based on a framework of PCK that has evolved over the past 30 years to organise understanding of the skills and knowledge of teachers (Shulman, 1986; Abell, 2008).

Once secondary pre-service teachers enter professional practice, they progress towards becoming experienced practicing teachers by expanding their knowledge bases and deepening their professional knowledge. The amplifiers and filters that affect their classroom practice become more strongly developed in parallel, and a useful review of the extensive literature in this area has been completed (Kind, 2009b). The growth in a teacher's topic-specific professional knowledge (TSPK) includes increased knowledge of instructional strategies, content representations, student understandings, and science practices together with altered habits of mind (Gess-Newsome, 2015). In addition, the progression towards more effective teaching is aided by teachers’ reflections on their students’ outcomes, feeding back to the amplifiers and filters that impact classroom practice. These elements represent the constructs of tacit and explicit knowledge, (Korthagen and Kessels, 1999; Davidowitz and Rollnick, 2011; Gess-Newsome, 2015) in which tacit knowledge is influenced by personal values and beliefs (holistic) and evolves in response to experiences gained in the act of teaching. Explicit knowledge can be rationalised, defined and transferred in the from of TSPK. Professional development plays a critical role in the preparation of teachers for primary and secondary classrooms (Supovitz and Turner, 2000) and there have been calls for it to focus on PCK (van Driel and Berry, 2012; Mavhunga and Rollnick, 2013). Reflective practice is already an embedded focus of a large majority of pre-service teacher preparation programs (Loughran, 2002; Korthagen et al., 2006).

The expansive body of research into PCK development has largely been based on teachers of children in the primary and particularly secondary contexts. Much less has been written about expert science teaching at the tertiary level, although some attempts have been made to characterize elements of such teaching using PCK as a framework (Fernández-Balboa and Stiehl, 1995; Davidowitz and Rollnick, 2011; Padilla and van Driel, 2011; Fraser, 2016), focussing on reflective practice (Kane et al., 2004), and examining behaviours and beliefs (Hativa et al., 2001). We have recently gained insights into the TSPK of a wide range of tertiary chemistry teachers that aligns with the consensus model of TPK&S (Schultz et al., 2018). We also found that, while there are many common features with secondary teaching in terms of the knowledge bases, instructional strategies, content representations and science practices, tertiary educators are less likely to have experienced any formal training in education (Barthelemy et al., 2013) and they are seldom taught to be consciously self-reflective in their teaching practice. The absence of the latter is significant in light of Loughran's conclusion (2002, p. 35) that ‘If learning through practice matters, then reflection on practice is crucial, and teacher preparation is the obvious place for it to be initiated and nurtured’.

Informed by the broad snapshot that we had obtained of tertiary chemistry teaching practice in Australia (Schultz et al., 2018), we set out to look for signposts of individual expert teaching practice through more in-depth interviews. We interviewed ten tertiary chemistry educators, all recognised as excellent teachers within their institutions, about their teaching practices in the context of a specific topic of their choice. We used the well-known CoRe instrument (Loughran et al., 2004), which we had validated for the tertiary context (Schultz et al., 2018) as the basis for the interview questions. The original CoRe questions were used rather than our adapted CoRe+ set of questions (Schultz et al., 2018) because we intended to give participants the opportunity to respond to the different stimuli provided by all of the original questions. Additional questions were included in the interviews exploring the source of teaching strategies, typical class size, any unsuccessful teaching experiences or initiatives, and what advice that the participant would have appreciated when they first started tertiary teaching.

The interviews revealed commonalities between participants in their journey towards teaching excellence within the lens provided by the consensus model for TPK&S (Gess-Newsome, 2015) and are the focus of this manuscript. Recent advice on interpretation of interview data from Silverman has been applied, such that long quotes that try to invoke the depth of human responses including repetition and pauses have been cited (Silverman, 2017). As recommended by that work, although we include some demographic data about our participants for the purposeful sampling, we use only the identities that they themselves invoked in the analysis. Because we are looking for general signposts of expertise, the responses to the individual CoRe questions are not all examined here; rather, each interview transcript has been examined for common features and these emerged in response to different questions in each case.

The research questions addressed in this manuscript are:

• What aspects of the teachers’ experiences signpost the development of tacit and explicit elements of TPK&S?

• What evidence is there that expert teachers reflect on student feedback to inform and modify their teaching practice?

Coding of the interview data was achieved through application of the same methodology that was developed in the previous study (Schultz et al., 2018) revealing the teachers’ individual TSPK. Details of their specific strategies for teaching and assessing each of their selected topics will be reported separately because substantial insight was gained regarding the influence of sub-disciplinary bias.

Methodology

This qualitative research study is based in semi-structured interviews built around the CoRes approach (Loughran et al., 2004) to explore participants’ perceptions of their journeys as teachers along with the factors that have influenced their practice. Interview participants were identified through publicly available citations of institutional teaching and learning prizes, national teaching and learning grants and awards, and participation in chemistry education activities (such as conferences and workshops). Purposeful sampling was applied, aiming for: (i) equal numbers of female and male participants, (ii) representatives across the five recognised sub-disciplines of chemistry, and (iii) a balance of teachers who are engaged in the scholarship of learning and teaching with those involved in traditional bench chemistry research but who nonetheless have been recognised as excellent teachers. Potential participants were initially contacted via email to invite them to participate in an interview. At this stage of the study one of the initially selected participants declined, and a replacement was identified. Following a positive response, in compliance with the institutional ethical approval granted for this study (QUT ID 1400000568), participants were then sent the interview questions along with an information sheet providing a full description of the aims of the project, that the interview would be audio recorded and transcribed, all data would be de-identified for the purposes of storage and publication and it was made clear that they could opt out of the study at any point. Informed consent to audio recording and inclusion of their data in this study was collected prior to the interview. It should be noted that, while currently employed at Australian tertiary education institutions, most participants had international experiences in terms of either their undergraduate, graduate, postdoctoral studies and/or first teaching experiences. Therefore this is not claimed to be a uniquely Australian study, the information and details of their institution or department has not been shared to protect the identity and privacy of the participants. All identifying references within the data have been replaced by ‘[identity removed]’. Demographic questions were asked at the beginning of each interview to capture data regarding: age range, length of time teaching, experience of teaching in different contexts, topics taught and who they felt had influenced their teaching. The full list of CoRe interview questions is provided in the Appendix, probing questions were adopted to gain additional detail and elaboration.

To avoid any potential bias in the responses, interviews were conducted by a project team member (CHB) who did not have a prior relationship with any participant and was not currently teaching. Each audio recording was professionally transcribed, then reviewed by the researchers to check for accuracy, particularly for technical terms. Due to the controlled environment (face to face or telephone) the quality of the recordings was high, leading to almost error-free transcription. Each interview was analysed separately initially applying deductive coding using NVivo software to analyse the interview transcripts, informed by themes that had arisen during our previous related study (Schultz et al., 2018). However, the semi-structured interview format and use of probing questions beyond those listed in the Appendix resulted in rich descriptive data. Additional themes that emerged inductively through this process have also been included in the analysis and results.

Due to the substantial amount of data collected, the diversity in themes and for clarity, the assessment strategies that were listed in response to interview question C12, which asked how participants check whether their students understand the topic, will be discussed in a separate manuscript.

Results and discussion

Ten excellent chemistry teachers, each with a minimum of 8 years of experience teaching at the tertiary level, have described their diverse journeys towards practicing with recognised expertise. We purposefully chose a sample with half of the participants characterised as Chemistry Education Researchers (CER) while the other half hold more traditional academic roles, conducting their research primarily in bench chemistry (BR). It is important to acknowledge that these designations are not exact because all of the participants had completed their PhD in bench chemistry research, and several in the BR group have also published in chemistry education research. Our purposeful sampling assembled a group identifying with diverse original chemistry subdiscipline backgrounds and included four female and six male participants. Given an open choice of topic for their CoRe responses, the participants selected ten different topics as the focus for their interviews; in every case these are related to the subdiscipline background of the participant. Table 1 summarises these characteristics of the interview participants and also includes a synopsis of their responses to two of the interview questions D5 (Has there been someone, teacher or colleague, who influenced your teaching significantly? In what way?) and C10 (Where did these strategies come from?).

Table 1 Experience and chemistry discipline orientation of the interview participants (CER = Chemistry Education Research academic; BR = Bench Research academic)

ID	Role	Years	Sub-discipline	Chosen topic	Greatest influence (Question D5)	Source of own strategies (Question C10)
I1	BR	>20	Coordination	Acids & bases	Only in what not to do	Own teaching
						Student feedback
I2	CER	8–20	Physical	Quantum mechanics	High school teacher	Knowledge of SoTL
I3	CER	8–20	Physical	Stoichiometry	Lecturer when I3 was a postgraduate tutor	Textbooks
						Teaching colleagues
I4	CER	>20	Bioinorganic	Intermolecular forces	Three chemistry education research mentors	Teaching colleagues
						Knowledge of SoTL
I5	BR	>20	Organic	NMR spectroscopy	Three lecturers as an undergraduate	Lecturers who taught with clarity
I6	BR	8–20	Physical	Colloidal stability	Academic developer	Teaching colleagues
						Knowledge of SoTL
I7	BR	8–20	Organic	Curly arrows	High school teacher and current colleague	Teaching colleagues
						Knowledge of SoTL
						Own learning experience
						Teacher PD
I8	CER	8–20	Analytical	Mole concept	All sorts of people	Textbooks
						Own teaching
I9	CER	>20	Inorganic	Atomic structure	Teaching in a team of colleagues in another discipline	Own teaching
I10	BR	>20	Analytical	Analytical approach	Three colleagues as a new academic	Own teaching
						Teaching colleagues
						Own learning experience

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During the interviews the participants provided extensive information regarding their teaching practices in general and also the knowledge that they have built up regarding their students across the span of their teaching careers. They shared a range of pathways through which they had become tertiary teachers and they described the variety of influences and experiences that have led them to their current teaching strategies. The majority of participants experienced the traditional route of being a tutor or laboratory demonstrator as a postgraduate before being assigned teaching as soon as they were employed as an academic, consistent with the common career path shown in Fig. 1.

Fig. 1 Typical career progress of a science academic illustrating professional development in teaching and the position of this project (reproduced from Schultz et al. (2018)).

The journey begins: initial tertiary teaching experiences and professional development

Based on the typical career path proposed in Fig. 1, the preparation that the participant academics had received when they were first given formal responsibility for undergraduate teaching was explored. Table 2 collates references by the participants from their interviews in which they described their first teaching experiences and reflected on the nature of any prior training that they had relied on, in some cases as part of a broader discussion rather than responding to a specific interview question such as question C14. Key phrases of interest have been identified by the project team, emphasized in bold in Table 2, however these have been retained within their original longer reference for context (Silverman, 2017).

Table 2 First experiences and support received by participants as beginning tertiary chemistry teachers

ID	Reference
I1	‘As a young academic I came here in [sic] 1984 and we hada two day course… we were told how to teach and it was taught by someone who walked up and down the class not facing us, telling us how to teach. And I sat up the back and talked to other people and we learnt more up the back than we did from listening to this clown tell us how to teach because clearly he didn’t have a clue.’
I2	‘I was just put in front of a class. That was it …I’d had formal [secondary] teacher training, and that actually was quite useful … If I’d been, if I hadn’t had that, I wouldn’t, I wouldn’t, my friends certainly hadn’t had any training of any sort’
I3	‘When I went through uni that was many, many years ago, lecturers only had one style, you know they just wrote on the blackboard, actual blackboard with chalk. That was the only style. They just talked… and that appealed to me. I mean, it suited with my, I guess that's all I knew so that was fine and so I thought, well I’ll just continue that and you know and the students weren’t understanding what I was saying and explaining and I thought, oh hang on what's going on here? This is the way I was taught. Come on, it should work …I started lecturing before I did my Diploma of Education… I definitely picked upa lot of strategies from my Diploma of Education, that I still use to this day so yeah, but when I first started actually … you were sort of thrown in the deep’
I4	‘I was very fortunate thatI had done a lot of tutoringbefore I started doing lecturing, so in other words, I had a lot of teaching experience, one on one, with struggling students, and I had the tremendous advantage that I was able to see and confront my own misunderstandings, too. So,through teaching others, I was able to realise what I didn't know, and then what they didn’t know, and so we both learnt as we went along, and so in some ways, when I started my teaching career properly I had a big advantage overmy colleagues who really had just done their PhD and then gone and done post-doc research and everything else, and then suddenly landed in an academic position and were handed a unit to teach. They didn’t have all of that background, so, the development I had was through all the tutoring. Idid a Diploma of Education, but that was worse than useless, as the only thing I did in that whole thing was I learnt a bit about assessments and aspects of assessment that are important, but all this, it was run by and for humanities-based teachers, so that wasn't very useful.’
I5	‘None at all becausetechnically my very first formal teaching class was while I was a postdoctoral fellow and I gave, I taught one component of lectures to what we might call the Honours stream. It was just assumed that you could do it, there. My next teaching appointment was at the University of [identity removed]. I think I remember the Dean, the Dean told me after my first lecture that he had walked past the lecture room and I was writing on the board with chalk and I was facing the students and I seemed to be doing the right things, so he said it looked okay to me as I walked past the door. I thought ‘Oh, thanks.’… There was anacademic who was employed to help new staff memberslearn how to teach, and I went to one of his sessions and he was talking about large group work. And his idea of large group work was about 20 or 30 students. So when I pointed out to him that the large group work for chemistry first year was probably 250 students, and I asked him for any particular tips that he had, he looked a bit flustered and said I don’t really know.’
I6	‘So before I first taught tertiary chemistry, I had athree day introduction to tertiary educationand it was really how to use the equipment, don’t overload students, be mindful of their workloads. It was all very practical stuff but nothing that was of a pedagogical nature and that's only something which I’ve learnt, what I have learnt with time just by happenstance really rather than a strategic approach by the university. There are different approaches that our university uses and I’m sure that others use and they, I guess they are varied in their success in informing what are teaching and research academics in how to teach properly and then enabling them to do so and rewarding them for doing so as well.’
I7	‘In terms of my very first lecturing experience, it was earlier again, which was in [identity removed].At that point I was teaching in parallel with this experienced academic and she gave me a fair bit of informal advice. That was on-the-job training. We planned the classes together and worked through ways to teach particular concepts. She had been teaching that particular class for a number of years and so I got informal training there. Then when I took up my posts in [identity removed] and [identity removed]I completed the Principles and Practices courses, although in neither case was the timing such that it was actually before I started teaching.It was in the first 12 to 18 months but just the way the courses were timetabled and the way my teaching was timetabled I did start lecturing before I completed the formal training.’
I8	‘Well the question's an interesting one because you have to say the first thing I ever did teaching was when I was a demonstrator way back when I was probably doing Honours or MSc at [identity removed] University, and that was completely untrained because we didn’t do it in those days …I did what was called at that stage Undergraduate Learning and Teachingat [identity removed] probably about 18 years ago… I’d been working out at industry and then I had a complete stop for six years while my kids were little and then I came in part time casual teaching and within that time I thought good idea, do it now, get it out of the way. So I did that which is a formal teaching thing…’
I9	‘Nothing at all,you are just let loose in there, yep, not at all.’
I10	‘I actually was buoyed straight from my PhD into a one year teaching position. And I was brought over by [identity removed] … who essentiallytook me under his wing as a mentorfrom a research point of view, but alsoas a teacher because I was part of the analytical chemistry teaching team with him.’

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As can be seen, most of the participants initially experienced mostly informal or no professional training to be a teacher. Participants frequently cited either mentorship or short institutional professional development sessions that were designed to prepare them for their teaching roles, although the latter appear not to have been particularly helpful in many cases and were also often completed after the participant had started their teaching. Indeed, the participants conveyed the idea that they were ‘let loose’ teaching undergraduate students with minimal or no training, and several indicated that their colleagues in similar roles had even less preparation than they did. There is no evidence that the academics who later moved into CER (I2, I3, I4, I8, I9) experienced any more defined preparation in teaching practice than those who have remained in BR (I1, I5, I6, I7, I10).

The insights that were revealed through these aggregated responses lend weight to our earlier finding (Schultz et al., 2018) that tertiary teachers receive little formal training and develop their PCK through classroom practice. In particular, the inadequacy of generic professional development courses in supporting chemistry discipline-specific teaching needs, paralleling a lack of discipline-specific professional development, was cited by several participants. This is further reinforced in the cited value of mentorship they received from more experienced people teaching in the same field; several participants specifically mention that they learned while teaching together with their colleagues.

Based on this finding and further data discussed below, we have constructed a model for tertiary TPK&S, deeply informed by the consensus model (Gess-Newsome, 2015), to recognise the different progressions within tertiary teaching practice that have been made explicit in this study (Fig. 2). The knowledge bases, including pedagogical and curricular knowledge, assessment knowledge and knowledge of students, are ill-structured prior to teaching practice for tertiary teachers, but develop during classroom experience, representing bottom-up acquisition of knowledge and skills acknowledged in our previous study (Schultz et al., 2018). The relative importance of the different domains is emphasised by relative size of the elements, hence classroom practice has a significant weighting. The chemistry sub-disciplinary content knowledge base is likely to be more developed than required for secondary teaching contexts due to the immersion of tertiary academics in their research during doctoral and postdoctoral experiences. Additional dimensions of this tertiary model (Fig. 2) are explored further in relation to the interview data below.

Fig. 2 Model representing the typical progression of tertiary teachers into their practice aligned with recognised influences, behaviours and practices that represent teacher professional knowledge and skill.

Enhanced awareness of strategies for supporting student learning

The participants in this study were sampled because they had been recognized as excellent teachers through institutional and national teaching awards; these are generally awarded based on evidence of practice including student feedback and teaching evaluations. In addition to clear practical outcomes for students that have already been demonstrated by the participants, their interview responses provided strong collective evidence of well-developed TSPK combined with a deep understanding of how students learn, which aligns with the consensus model of TPK&S (Gess-Newsome, 2015). Characteristics of tertiary teaching contexts that differ from secondary teaching were cited by all participants, such as very large classes, adult students who choose whether or not to participate in particular activities, diverse levels of preparation among the students, and using technologies to engage students. These combine to indicate that tertiary teachers are presented with classrooms contexts in which they practice that are quite different to those that secondary teachers typically practice in (reflected in Fig. 2 through the emphasis on classroom context in Classroom Practice). The dynamic nature of class size (cohorts of several hundred students in first year courses to 20–30 students in third year) and randomly assigned teaching spaces (ranging from traditional tiered lecture rooms to contemporary flexible active learning spaces) each semester presents challenges to tertiary teachers in being able to monitor their students’ individual understanding. Table 3 collates the references from participants that describe their approaches to obtaining immediate feedback from students on their understanding, and implementing active learning pedagogies and student-centred strategies in large class teaching within the university context.

Table 3 Teaching context, instructional approaches and monitoring learning

ID	Reference
I1	‘They had the PowerPoint, they had their notes, butwhat they then had is me developing a point. So I might have for example a, I might do a buffer problem or I might just explain something but it would all be then on the visualiser andthey’d have to write it down and they’d have to engage in doing thatand then that's where the questions would come from. I’d get more questions from what I was doing on the visualiser than what I would from the PowerPoint.So that, and I know it took me a long time [laughing], a long time to get to that strategy but it was a, I could never write on a blackboard because my writing's so bad and my back was to the class which I never liked,I always liked to engage the class, but that worked for me really, really well in the end and I, that's what I enjoy doing, is to come out of those classes thinking geez I enjoyed that.’
I2	‘… I would lecture for five or 10 minutes and they would be working, we have work sheets, which they picked up as they come in. They work on the worksheets.Then we either have a discussion, oral discussion, we might have, we might use a response device, like their mobile phones to feedback answers… We’ve introduced things like response devices, and passing microphones around in order to facilitate discussion.’
I3	‘Yeah, what I do isI use clicker questions in a lecture, so multiple choice you know they’ve got the clickers and I see the class distribution so I can see how many students percentage-wise, got that right and then if they don’t, then I go through it again.That really helps me to get the feedback from students about their understanding. I mean, I use it for other topics as well but yeah this will be one topic I use it for in a big class’
I4	‘… I’m dealing with typical class sizes between 200 and 400 students at any one time, and so the most powerful strategy, I suppose, one that I haven’t really talked about before, isusing audience-response technology, that you can use clickers, just the hard clickers where they can answer multiple-choice questions, but do it confidentially so they don’t have to put their hands up and be wrong, if you like, but you can, through very careful use of questions, and not to overuse this strategy, but by carefully constructing questions that provoke thought, that really do probe whether they’ve got understanding or not, this is a very useful strategy for large classes like I use …the other one, I think is drawing, now, that's much harder to get students to accept and spend time with, because they hate, many students hate drawing. They, in fact, they get quite antagonistic towards it because they haven’t been asked to do it before. They’ve been asked to do calculations, they’ve been asked to write explanations, they sort of expect that, and some of them like doing calculations because they can do it on a calculator, but drawing, why do I have to draw? They’re embarrassed by their drawing or their inability to draw…’
I5	‘Yes, I started off about eight or ten years ago setting these classes up as small group work… So yes, while I’m walking around if I see students working by themselves I am trying to get them to work with somebody else. So sometimes I photocopy the problems rather than expecting students to download them from Blackboard, and if I do that I take in enough copies so that students have to share. So thatthey’re forced to work together…when I’m going around if I see students either withdrawn and particularly if they don’t seem to have much written down. Even if it's a group of say two or three students who just seem to be stuck on the first problem and haven’t written much down. So they’re quite good about letting melook over their shoulder in other words, and see how they’re progressing with the problems. So it's quite straightforward as I described to put them in the right direction by giving them hints.’
I6	‘Three years ago I changed my method of teaching to bea team based learning approach where in fact as teams they are responsible to each other within the team for their level of engagementor for what they put into that team and if they don’t put in what the team thinks is useful then they get marked on that, their peers mark them on how much they’re contributing to the team's goals. So rather than me as the educator saying you need to do this and you need to do that, in fact the system is such that as a team they’re responsible for a certain outcome and the team must achieve that outcome and so they need to work together. For the students who are slackers, I shouldn’t say slackers, who don’t put in as much as the team expects of them then there is peer pressure to increase their level of input and their engagement and if the students don’t then the team members get a chance to reflect upon that and give them a sort of team work score.’
I7	‘I try to encourage active learning in the lecture theatre, soI'll talk about a concept and then ask them to look at some examples and work through them on their own. We do that in a number of different classes over the whole course. So that first-year course I'm talking about is 20 lectures. We introduce the curly arrow concept either in lecture four or lecture seven, depending on the way the course split. Thenwe basically revisit it every lecture thereafter. For 13 or 14 lectures, it would come up in some different form.’
I8	‘In the lecture theatre the best strategy there, where you’re confronted by all the constraints of the lecture theatres, isto stop and do stuff with the students, walk around amongst them, see what they’re actually doing… And out of that you might go back and address some aspect of it and revisit it or something like that or you might point them to some tools to use to work out some other aspect. So in the lecture theatre it's very much for me a case of stopping and going and seeing what they’re doing and if you don’t then clearly you don’t know…You can put up multi choice questions and see just hands upbut to this stage I haven’t done that strict quantitative gathering of data from answering questions using clickers or real question time or something in Moodle or something like that.’
I9	‘Well, they’re doing problems and activities in the session, so you hopefully get some feedback, although, obviously, it's difficult with 180 of them.I use clickers, so that can give you pretty instant feedback, and then it's followed up with tutes or workshopswhere you’ve got smaller groups of students and they’re working through questions and problems, so that's an opportunity to get a better feel for where the areas of difficulty are.’
I10	‘We actually have in our classroom people who are second year chemistry students, but we also have third year chemical engineering students. And it's balancing those expectations. But also we have differing cohorts of students, we have regular chemistry students, we have some environmental students, we have the chemical engineering students. And it's not so much a difficulty as a challenge, to ensure that I can speak to each one of those groups by providing the appropriate examples … I tell stories, essentially. I tell stories. I turn everything into a story in some way. … That you can link it to stories that are in the media, personal experiences, my own personal research experience. The student's own experience. So it's shared. So while I thought I was a straight forward didactic teacher, you know I just stood there but I’m not,I asked students, alright who's got experience of this, and then I use a narrative form to get that across, and it seems to work.’

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The participants all referred to using questioning and formative feedback to evaluate their students’ understanding and difficulties while learning in their classrooms. Different levels of engagement with using technology (ranging between clickers to putting hands up) to achieve this was evident depending on their teaching style and context (including class size). Encouraging students to engage in discussion in class was a second common thread that emerged through the participants’ narratives. This aligned with their common focus on reducing the amount of chemistry content to enable more application of concepts. This theme is expanded on below. Thus, we identify the first signpost of tertiary teaching expertise from this study as seeking and receiving feedback from students and encouraging active engagement during class time.

Depth of curricular and content knowledge

Content lies at the heart of tertiary teaching, because students are assumed to be adult learners who are presumed to be competent in managing interpersonal and other skills that are typically taught in parallel with content at high school (Coetzee, 2014). However, evidence indicates that a focus purely on content delivery leaves many students behind in learning, especially in mixed classes with a range of backgrounds (Deslauriers et al., 2011; Stains et al., 2018). Expert tertiary teachers manage to patch holes in student prior knowledge while maintaining a focus on teaching complex content. Unlike the years of compulsory schooling (Reid, 2005), there is no set curriculum that tertiary teachers follow. This has been recognised in attempts to agree on standards and benchmarks both in Australia (Ewan, 2010; Jones et al., 2011) and overseas (Tuning Project, 2007; Pinto, 2010).

As a consequence, each discipline is taught through a somewhat different curriculum in each institution, and the academic staff have some flexibility in choosing the exact nature of the content and assessment in their teaching i.e. there is no prescribed syllabus. However, for chemistry the content taught at first year is largely common (Holme and Murphy, 2012; Schultz et al., 2013), while at higher levels there is more diversity representing the disciplinary expertise and biases of the specific academic staff members.

Although curricular and content knowledge are separate bases in the model in Fig. 2, they are considered together here because application of this knowledge was found to be intertwined in our participants narratives. That is, their understanding of the content that they were teaching was deeply linked to their understanding of how this fits within the whole chemistry curriculum. In the absence of a formal syllabus or curriculum and professional development early in their careers, this awareness can only have been developed through their iterative experiences in tertiary teaching across multiple levels. Hence the model shown in Fig. 2 emphasises this experiential development of knowledge and skills through the bi-directional dashed arrows on the right hand side.

The participants were each required to select a topic on which to focus during their interviews (Table 1) and, while they all showed great awareness of the importance of constructing understanding in core concepts, there was a noticeable distinction in the choice of topics made between the CER and BR academics. The latter chose topics more aligned with their disciplinary professional skills and formalisms: analytical thinking, NMR spectroscopy, curly arrows, colloidal stability and acids and bases (in the context of the practice of other disciplines – see below). The CER teachers opted for more fundamental concepts: atomic structure, quantum mechanics, intermolecular forces, stoichiometry and the mole concept. This is an interesting outcome perhaps attributable to CER group of participants being more focussed on fundamentals through their engagement with chemistry education research.

Several participants mentioned strategically reducing the amount of content that they included in their teaching to create time to focus on concepts, and some were quite specific in details of how they have reduced the amount of “stuff” that is covered as their experience increased. References extracted from participants responses, provided in Table 4, support this theme that emerged inductively from the data. A specific question that elicited this information was not asked in the interviews yet more than half of the participants referred to this practice. This reflects their deeper knowledge of the whole curriculum of the undergraduate chemistry (or other) degree as well as their deep understanding of the specific content that they are teaching.

Table 4 Changes in teaching approach through reducing content to enable the focus on concepts

ID	Reference
I1	‘When we first started teaching this here is when I first started teaching it years and years [ago].We used to do it rigorously. We would go from strong acids, strong bases, weak acids, weak bases, we’d go all the way through and we’d do calculations on titrations and all that sort of thing andreally over the years it's become obvious to me that there are only about three key principles that they need to know from this chemistry. And all of it comes back I think to understanding equilibrium and buffers. Because if you understand buffers, which involves understanding weak acids and weak bases, conjugate acids, conjugate bases, equilibrium and things like that,if you understand that you can immediately understand titrations, you can immediately understand all the concepts that you need because they’re encompassed in the concept of a buffer… So in my last couple of years of teaching this stuff, I cut out an enormous amount of stuff about, you know, calculating the point on a titration curve for a weak acid, a weak base, because it's pointless because all you’re doing is buffer calculations. So that's what I boiled it down to and I thought if they can walk out of that class with an understanding of how to do a buffer problem or even understanding what a buffer was and how it worked that was enough.’
I2	‘I guess, the struggle is totry to teach and get them to think about things conceptually when, to a very strong student, or a very mathematically literate student, it's almost easier to just to rely on the maths. Because the maths just shows you everything, and gives you the answers without you really having to understand the physical basis.’
I4	‘The difficulties and limitations are as a result of not spending sufficient time on getting them to think about this world, and spending too much time on doing, you know, we’ve got to spend some time,but you can’t spend too much time, I think, on a lot of the ideas that we do teach, and doing calculations and things that, really, no one else does, it's really something that's done almost like it's make-work-type stuff.’
I5	‘25 years ago, the norm was that you just stood and wrote on the blackboard or wrote on the overhead and you had a certain amount of material to get through, and it was just up to the student to be able to keep up and if not to study the textbook, and I think we all know that teaching is a bit more sophisticated than that these days…I think the way we teach first year chemistry is hugely improved over even 20 years ago. There was just such a heavy emphasis on you must get through this content because they need to know that for the second year content.There was just an inappropriate amount of content, so one of the biggest changes has been the consolidation, the coherence if you like now of first year chemistry programs. And it's got a much better structure to it, sort of comes from communication and teamwork… first year was just a nightmare 20 years ago. I don’t know how I survived actually, but I did. And I still enjoy teaching first year now.’
I6	‘I was really focussed on them just becoming content experts and I did it that way for three years and I was quite happy at the time they were becoming fantastic content experts, then I realised that in factI should be trying to get them to do more or they’d just be content experts in my unit.’
I10	‘I want them to stay awake, and so we don’t go into the absolute detail of absolutely every single thing they need to know. Soit's not the heavy, it's not heavy on content but more heavy on reason. Why you do it.’

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The second signpost of tertiary chemistry teaching expertise that we propose is thus awareness of the importance of an increased focus on concepts requiring a concomitant reduction in content. This appears to be triggered by a comprehensive understanding of how their content fits into the whole tertiary curriculum; as I5 said “And it's so essential if you are in the middle of a discipline to have a really well developed sense of what your colleagues around you are teaching, so that you can make connections.”

Experiences and advice informing classroom practice

In considering the form of discipline-specific professional development that might be appropriate for novice tertiary teachers, two interview questions C13 and C14 were included to elucidate what participants felt would be important. Selected parts of their responses are included in Tables 5 and 6 with their key advice emphasized in bold. Some of these responses were provided in general discussion of other questions during the interviews but have been included here.

Table 5 Responses to question C13 ‘Have you ever used or experimented with any teaching strategies or methods which have NOT been successful? Please give an example’

ID	Chosen topic	Strategy that didn’t work
I1	Acids & bases	‘Ohclickers were never successful with me, I could never, I just thought they were stupid. I tried them but it just didn’t work with me. In the end I used to say, I would put a problem up and I’d say put your hand up, go like that, because that was as good as a clicker.’
I2	Quantum mechanics	‘The worksheet type of approach … so the students are working for almost the entire lecture under the guidance of the team of teaching assistants that are in the class. Which I think works fine in our tutorials, but I don’t think in a lecture, I thinkI just find in a lecture it all goes a bit, the students get off topic pretty quickly… I used to give them, perhaps, 10 minutes to work on a problem, now I probably only give them two or three minutes. I find that concentrates them and prevents them just talking about the State of Origin or whatever it is that's on their mind. We just need to keep changing the activity, rather than have extended activities.’
I3	Stoichiometry	‘I use, I don’t know if you can call it a teaching strategy. I guess it is using analogy for teaching, electron configuration and I use the analogy of atomic hotel to help students understand how electrons go into different levels … what I have found isfor some students they love it. They get it and then they can, relate it to their electron configurations. For other students it's been that they said oh, they’re getting more confused! … they just lose the idea, not the idea but the link I’m trying to make, there's nothing for them at all and they get frustrated so, it's been interesting that some strategies work perfectly for some students and are a total failure for other students.’
I4	Intermolecular forces	‘Yes, I try very hard to teach with groups and peer discussion, and in fact I’m continually doing that, but I’m not sure I’m as good as I could be at that, and I think I’ll die before I really am any good at it, because there's so much time I need, becauserunning groups and getting people to work together, and keep people going and not chattingand so on, it's hard.’
I5	NMR spectroscopy	‘I started off by giving them a small test based on their second level content, which I then graded and then I put together groups where I had strong people, medium people and weak people in the same group. So the idea that it would be sort of peer group learning, and they would work together.It didn’t work terribly well because they tended to migrate to work with a friendrather than… so unless I enforced the groups, they preferred to just sit with their mate. And soI followed the path of least resistance, which is that as long as they’re doing it as a group activity and not trying to do it just by themselves…’
		‘I once, because I had an extra spare lecture, decided to go in and tell the students about why I’d become an organic chemist, and they didn’t appreciate it basically … I thinkit was because it was not content and they hadn’t been prepared for it, and perhaps told that it was optional. So they all gradually started walking out, so I felt that it was a complete waste of time and I never did it again. But at the end of the class one student came up to me and said that was magic.’
I6	Colloidal stability	‘In the second year that I ran this team based approachI didn’t do the peer quantitative evaluation of each other's input… I did it the first time and everyone got their feedback and then because it was a success that the feedback had worked when I ran this teaching approach the previous year, that's when I thought that's fine, this will work and I didn’t bother to do it the second and third time and that wasn’t successful at all. Unfortunately there were students coming to me towards the end of semester saying they’re doing all the work and the people in their group weren’t.’
I7	Curly arrows	‘I would run the lectures, I'd run the tutorials, I put worked answers up on the … this is pre-Blackboard. I put them up on my website.I put a password on them and the password was only available in the tutorials, so trying to promote student attendance at the tutorials by restricting access to the worked answers. How we gauged whether that was successful or not, I don't know what it did to attendance but it created some grumpiness on the part of the students, so I stopped doing that.’
I8	Mole concept	‘I’m just remembering back to the workshop sheets that we used and one of the stoichiometry onesI’ve modified because the tutors had come back and said to me, this is a bit messy, they don’t respond well to this, they’re not quite understanding what you’re trying to get them to doas they work through this sequence of questions.’
I9	Atomic structure	‘I got students to work in groups on something, andI let students select their own groups, and that was a disaster,and it's the only time I’ve ever allowed students to select their own groups, because you get all the bright sparks working together and all the lazy articles working together, and it didn't work very successfully, so I learnt from that.’
I10	Analytical approach	‘A long, long time ago I did try some sort of spot tests, and that didn’t work out very well.It was more trouble than it was worth and it was too much of the, hey do this you’ll get some marks, and I dropped that a long time ago.’

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Table 6 Responses to question C14 ‘What advice do you wish that someone had given you when you first started teaching?’

ID	Advice wished for
I1	‘Never be one lecture ahead of the students. Always write your course before the semester starts so that you know what the flow is and what the connections are. If you’re always writing one lecture ahead of them you have no idea what's coming in the future therefore you can’t make the connections across the whole set of 10 lectures or whatever.I think it's very important to be able to know what's coming, know what's gone behind and know what you’re doing at the moment fits both ways.’
I2	‘So the first thing that I really stress that people do, is that they actuallygo and watch some classes. I think that's the most important thing. When they’re coming straight out of a postdoc, or they’re coming straight out of the Research Centre, and then, they’re told they’re going to be lecturing 300 first year students, they’ve got to go and sit in the back of the lecture theatres for a few weeks, and that’ll assist …’
I3	‘I know it seems obvious now, butI actually can really pick up on the fact that students have such diverse learning styles. … I think it would be good if someone told me that at the start, but as I said because I ended up doing my Diploma of Education that opened my eyes to that and that's when I started to utilise different strategies and I appreciate that not everyone is going to understand one way of, my teaching way.’
I4	‘Just teaching through intuition is not good enough, and teaching the way you were taught is not good enough.You need to have a scholarly approach to teaching and learning based on the way we know that students learn, and so there's stuff you have to engage with.’
I5	‘You had to start from scratch writing your own lectures, even in first year. You were sort of told that you had to teach A, B, C, D but none of the detailed content was there. So the teamwork approach that we have now is hugely better and hugely more supportive of new staff. It's not as much advice, what was missing was this sort of information link, how do all these bits join together that people just weren’t prepared to share. Andit's so essential if you are in the middle of a discipline to have a really well-developed sense of what your colleagues around you are teaching, so that you can make connections.’
I6	‘Talk to as many different people as you can about their teaching approach and start sitting in on classeswhere you have either heard there's very good student feedback on how the classes are going or where they’re getting very good university awards or been recognised by departments or where they have very good classes. So rather than teaching that little black box which we tend to do in isolation, just sitting in on other people's classes to see what other people are doing well or not well and learning from that.’
I7	‘I recognised that I was quite focused and fairly nervous the first few [times]. I did a lot of preparation to the extent of going to the lecture theatre the night before and working out where I was going to stand and so on. But equally with a bit more time I'm more relaxed and able to consciously enjoy the interaction more than I did when I first started. That makes for a better experience with the students. So I guess in terms of advice, if you canrelax and enjoy yourself and enjoy the interaction and the communication with your students, then that will make for a better learning and teaching outcome, I think.’
I9	‘Oh, tofocus on the students, to focus on what they’re doing rather than what you’re doing, I think, because when you start teaching you’re so obsessed with preparing your lecture, preparing your presentation, thinking about your performance, and I think you should try and twist that round and focus on what am I going to get them to do? What are they going to be doing? What are they going to get out of this? How are they going to feel when we finish this?’
I10	‘Probably to think more deeply about assessment… We do an awful lot of focus on teaching but realistic, authentic assessment that actually engages the student and actually about that's a tougher ask … I set a lot of essay type assignments … But when I started doing this I used to get very poor results and it's taken me a little while to realise is that the students weren’t understanding what the questions were.’

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Common themes that arose within the identified unsuccessful strategies (Table 5) related to challenges in managing group work in class and ensuring that students stayed on task. This appeared to be associated with implementing tasks that students did not value (in many cases related to course marks or expectations). While many had struggled with the process of implementing effective group work in their classes, there was a strong commitment to making this strategy work. In particular, participants I5 and I6 expressed appreciation of the potential learning benefits for students gained through group discourse.

In terms of the advice that they wish that they had been given (Table 6), the participants adopted a range perspectives in responding to this question. Most were pragmatic, discussing planning and preparation for teaching, including recommendations to observe colleagues and thinking carefully about what students will do in class. This reinforces the first signpost identified above, that expertise relates to knowing students and obtaining feedback of their level of understanding during class. It is interesting that all participants described classrooms built on constructivist approaches even though most had not been trained in formal pedagogies, illustrating the impact of their depth of own experiences and reflections on their practices and student learning.

Indeed the participant responses in Tables 5 and 6 demonstrate a range of influences on their pedagogical knowledge including watching or working with peers, drawing on research literature and working out strategies on their own. This reinforces our thesis that, for tertiary chemistry teachers, tacit knowledge has grown primarily through their teaching experiences while the explicit component is through transfer of practice in informal settings rather than formal training (Table 2). This versatility in informing their own practice represents the third signpost of expertise in tertiary teaching and is summarized in a reflection by participant I1:

My approach won’t always work for everybody but it might work, parts of it might work for some but parts of other people's strategy might work for me, but it's a matter of sharing those strategies … But yeah the strategies just come from experience I think.

Reflective practice in tertiary teachers

A theme that arose inductively from the interviews was that participants expressed willingness to modifying their teaching approaches through reflection on their practice and the learning needs of their students. This evidence aligns with the importance of classroom practice informing tacit knowledge. To explore this theme further, we adopted the approach taken by Kane et al. (2004), based on the work of Hatton and Smith (1995) to categorise teacher reflection as one of four types: technical reflection, descriptive reflection, dialogic reflection and critical reflection. It is important to note that our interviews were based around the CoRe so asked different questions to those used in the study by Kane et al.; in particular, their participants were recorded teaching a class and then taken through stimulated recall so it is not surprising that some categories of reflection were found more often in that study.

All 10 of our participants described at least one example of their practice in terms of how a strategy or activity that they had used worked and what their students did in response, which represents descriptive reflection. In contrast, only four participants engaged in technical reflection, which is characterized by a focus on practical approaches (mention of adaptation based on the resources available) and how to improve processes in future. There were also four participants who engaged in dialogic reflection where they expressed having a conversation with themselves regarding what was happening in their teaching:

You know I’ll, even at the end the night before I’ll sit and flick through, you know, that's after having done it for 30 years, I still flick through and say, you know, no, and I change things and stuff. Just a matter of well yeah I need to change that … (Participant I1)

… so I thought, well I’ll just continue that and you know and the students weren’t understanding what I was saying and explaining and I thought, oh hang on what's going on here? This is the way I was taught. Come on, it should work. (Participant I3)

Kane et al. (2004) noted that critical reflection (considering social, political and cultural forces as indicated by Hatton and Smith, 1995) was least frequently observed amongst the tertiary teachers that participated in their study (three of seventeen). Analysis of the transcripts showed that two of our CER participants demonstrated some form of critical reflection. One related to awareness of teaching practice in the context of scientific literacy:

The most important thing is that anyone who has this molecular-level view of life, could then, perhaps, be less inclined to think in terms of magic, to think in terms of, oh, things are happening by supernatural means, and what I mean by that is that, well, for example, crystal power, there are people who believe that their crystals can be a source of power. Now, but with a well-developed molecular-level model on chemistry, you realise that very, very quickly, that cannot possibly be true, and so therefore, we can avoid having people spending a lot of money and being exploited by being sold big crystals in the thought that it might heal them from cancer or something like that, see what I mean? So, it's really understanding more and more about molecules enables you to not have to resort to superstition or to other things to be able to explain why things occur the way they do, and I think that's a really big idea, that knowledge of the world enables you not to have to resort to supernatural, that's beyond natural, explanations for why I was cured of my cold, why something happened and something didn’t. (Participant I4)

The second related to the diversity of their students, particularly international students who have English as second language:

I mean yeah of course English is the obvious barrier I guess and yeah, like chemical jokes, yeah it could be, but I don’t know. Yeah, I haven’t and maybe yeah like if students come from another country maybe they don’t have that in their teaching, so they might think this is a bit strange. Why was she using jokes with them? You know. (Participant I3)

A discipline-specific form of reflection was also observed during the interviews of four participants who are recognised CER academics (I3, I4, I8, I9), they demonstrated strong reflection on their practice in terms of their own thinking about students’ thinking, particularly in regard to what is not visible to the eye. This practice demonstrates their well-developed chemical epistemology and these teachers clearly base their own practice around developing students chemical thinking (Chittleborough, 2014). The importance of students having a correct mental model of what cannot be seen by eye has long been recognised (Johnstone, 1991) and forms the cornerstone of chemistry education. We propose that this represents a subset of critical reflection specific to our discipline. All four references from interviews are included here to illustrate how embedded this feature of chemistry education is in teaching design and practice for expert tertiary teachers.

Yeah. I mean you can see the precipitate forming but how do I convince them that one test tube has silver ions and the other one has chloride they’re not coloured ions and so on… So, from what you see to the invisible, what is the molecular level. That's the hard part. But for me, I do visualise it. I don’t know if students do. And that's why chemical equations are so difficult for them. (Participant I3)

I think philosophically, it's an incredibly-powerful idea, and quite counterintuitive, that, in fact, my consciousness, the way [redacted] is, and the way you are, and thoughts and all of that, are just simply manifestations of molecular interactions, and for a lot of people, that's a horrible idea, and so I think it's important for students to have a really well-developed idea of the molecular world, so they can make up their own mind about whether they think there is something beyond that, which is not accessible to science. (Participant I4)

… yes, their thinking. So you’ll say to them, I have a gram of gold, it's very heavy. So we need to understand that there's fewer atoms in that gram that there would be in a gram of hydrogen so you can begin to get them to visualise in their mind as you’re talking it through. They need to get that thinking the right way round. It's heavy, so in a certain mass there will be fewer which means if I want a particular number I take a larger mass. Hence the molar mass of gold is much larger than the molar mass of hydrogen. So they have to set up that train of thought and you can see that clicking into place sometimes when you’re talking to them but I think that their thinking is, they’ve got to go from thinking proportionally to actually inverting something because something is heavier I need a larger mass to get the same number. I’ve found that talking them through that apparent inversion of thinking has been difficult. You’ve got to address that thought. I need a certain number. I’m going to have to go to a larger mass because they weigh more. And sometimes you can use analogies like everyday objects and there are a variety of things you can do in that way. (Participant I8)

Well, I suppose it's all very abstract. It's difficult to give it a context, I suppose, a real-life context. I don’t know, really, I suppose just because it's a very abstract idea, really, and there are also sometimes, students find it difficult because you’re giving them a more complex model than the model that they’ve come to university with, and students get a bit distressed about, oh, you’re telling us everything we’ve done before was wrong, and I think what I try to get students to see is that we use models and you use a model, while it works, then when it doesn’t work you develop a more sophisticated model, and what we’re doing now is developing a more sophisticated model of the structure of the atom, of bonding between atoms, so I think they found that difficult, the fact that you’re putting aside the model you used previously and developing a more sophisticated one, and I think that's something, it just knocks their confidence a bit, and I think we’ve got to convince them that, actually, what your teachers told you at school wasn’t wrong, it's just that this is more sophisticated, that science is all about building models to explain reality. (Participant I9)

We therefore propose that the final signpost of tertiary chemistry teaching expertise is engagement in purposeful reflective practice and a willingness to adapt teaching approaches, constantly endeavouring to find ways to support student learning. This is not a skill that has been taught but has been acquired through practice and informal networks.

Conclusions

Characteristics of tertiary teacher professional knowledge and skill

The interview data has provided substantial insights into tertiary chemistry teaching knowledge and skills through the shared journeys of these ten recognised excellent teachers who did not follow a single route but arrived at similar destinations. Their perceptions, experiences, strategies and knowledge of students align strongly with the elements in the consensus model (Gess-Newsome, 2015). This overall alignment validates the preliminary interpretation of the characteristics of tertiary chemistry teaching captured from a wider sample of Australian teaching academics (Schultz et al., 2018). There are, however, critical differences shown in Fig. 2 that can inform the development of tertiary-specific TPK&S through professional development. The significant differences between the secondary and tertiary contexts are likely to impact on classroom practice.

The evidence collected in this study in response to the two research questions enabled distillation of four important signposts of tertiary teaching expertise that demonstrate the interwoven nature of tacit and explicit elements of TPK&S:

• expertise in seeking and receiving feedback from students and encouraging active engagement;

• awareness of the importance of an increased focus on concepts and reducing content;

• development of personal classroom strategies from experience; and

• purposeful reflective practice and a willingness to adapt teaching approaches.

The first two signposts involve knowledge bases that can be made explicit in the form of specific advice and teaching strategies that can be transferred between individuals. The third and fourth signposts represent personal PCK and skills amplified by personal orientation (Fig. 2) since our evidence indicates that participants’ understandings and decisions are dynamic. This is tacit knowledge, developed through reflective practice in the classroom, and is person, topic and context dependent (Loughran et al., 2008; Gess-Newsome, 2015).

Previous studies have explored what tertiary teaching excellence represents in terms of beliefs and practices. Indicators that were reported included reflective practice, preparation and organization, connecting to students by engaging their interest and stimulating motivation, enthusiasm and clarity of explanation, and strong interpersonal relationships with students through respecting them and encouraging their success (Hativa et al., 2001; Kane et al., 2004). We have made these elements of good teaching practice explicit for excellent tertiary chemistry teachers through applying the lenses of TPK&S and PCK in this study to capture the central role of their reflections on their teaching in their practice.

Implications for practice

While it is impossible to accelerate the process of acquiring individual tacit knowledge through experience and reflection, there are several aspects of the journey towards developing teaching expertise that have emerged from this study that can be made explicit. Firstly, discipline-specific professional development is clearly required in the very early experiences of tertiary teaching. Given the timelines that are commonly experienced when starting a new academic position, this would be most optimal during the doctoral or post-doctoral stages of the career (Fig. 1). Until now, there has been little focus on training novice tertiary teachers in practice, because a low percentage of doctoral candidates progress to an academic role. However, many doctoral and post-doctoral students have already decided that they are aiming at this career and it is incumbent on their institutions to provide them with the opportunity to engage in discipline-specific tertiary teacher training. Many institutions already offer generic programs that early career academics can access, including literature frameworks and current understanding around student learning, cognitive load and instructional design. Ideally, these should be connected to disciplinary training that provides specific strategies for teaching different chemistry topics, including making the ontological framework that the three levels of chemical representation of matter provide more explicit (Chittleborough, 2014), taking account of the tertiary teaching context including large classes and applications of technology.

Second, the critical importance of seeking feedback from students regarding their thinking during class must be emphasised to novice tertiary teachers. Discipline-specific examples of good practice for obtaining feedback, such as using concept check questions using clickers, can be shared at all levels of professional development, including with experienced tertiary teachers who have not yet adopted this technology.

As stated by I9, novice tertiary teachers should be encouraged to shift their focus from what they will be doing in the classroom to what the students will be doing while they are planning their activities. The difficulties of keeping students focussed during class should not be underestimated; this is apparent in many of the participants comments (Table 5). Therefore, specific approaches such as very short in-class activities, ways to form groups, and discussions with teaching colleagues to ensure sequences are logical for students should be adopted. Finally, we found that tertiary chemistry teachers who have a research focus within chemical education research emphasise the development of correct mental models at the molecular level. This should be a key feature of discipline specific professional development that shares modelling practices.

Conflicts of interest

There are no conflicts to declare.

Appendix

Demographic questions

D1. What is your age range?

• 25–34

• 35–44

• 45–54

• 55–64

• 65 and over

D2. How long have you been teaching tertiary chemistry?

• 0–2 years

• 3–7 years

• 8–20 years

• Over 20 years

D3. Have you ever taught chemistry in any other environment, for example a high school?

D4. Which chemistry sub-discipline(s) were you trained in or do you most identify with? Is this the area that you do most of your teaching in?

D5. Has there been someone (teacher or colleague) who influenced your teaching significantly? In what way?

CoRe and supplementary questions

C1. What topic do you think is very important in learning chemistry?

C2. What are the big ideas for that topic that students should know?

C3. Choose one year level that you enjoy teaching – what do you intend the students to learn about this topic at that level?

C4. Why do you think it is important for students to know this?

C5. What else do you know about this idea that you do not intend students to know yet at this level?

C6. What difficulties and limitations do you think are connected with teaching this idea?

C7. What do you know about students’ thinking that influences your teaching of this idea?

C8. What other factors influence your teaching of this idea?

C9. What teaching strategies have you used and why did you choose them to engage students with this idea?

C10. Where did these strategies come from?

C11. For this example strategy or tool, what is the typical class size in which you use it?

C12. How do you find out whether students do or don’t understand this idea?

C13. Have you ever used or experimented with any teaching strategies or methods which have NOT been successful? Please give an example.

C14. What advice do you wish that someone had given you when you first started tertiary teaching?

Acknowledgements

We are very grateful to the ten participants who generously shared their expertise and time. We also thank our reference group of John Loughran, Roy Tasker and Bob Bucat. Support for this project was provided by the Australian Government Office for Learning and Teaching (SD14-3737). The views in this manuscript do not necessarily reflect the views of the Australian Government Office for Learning and Teaching.

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