The complex nature of teacher decision-making and practice, nessecitates the use of multiple data sources in order to make sense of what teachers know, what they believe, what they do, and the reasons for doing what they do (Baxter & Lederman, 1999; Hume & Berry, 2011, Kagan, 1990). The data sources often used in the assessment of teachers’ knowledge include semi-structured interviews, classroom observation, lesson plans, video stimulated interviews, reflective journals and researcher’s field notes (Park & Oliver, 2008; Rollnick et
al., 2008; Hanuscin et al., 2011).
Interviews, whose purpose according to Kvale (1983, p.174) “is to gather descriptions of the life-world of the interviewee with respect to the interpretations of the meaning of the described phenomena”, is one the most common and powerful ways used to try to understand human beings (Fontana & Frey, 2000). The focus of my study was not only to identify the knowledge the teacher draws on but also to understand how this knowledge influences the decision he makes with regards to practical work. Just observing the teacher in the classroom could not provide the depth of data required.
There is a wide variety of forms of interviews but the semi-structured interview seemed to be the most appropriate choice for conducting with the teacher and learners. The pre-planned questions ensures that the researcher probes particular areas of interest but at the same time this type of interview allows the interviewer the flexibility of deviating from these questions, potentially providing a greater depth and breadth of data (Fontana & Frey, 2000). Researcher bias and the effects of social cues are unavoidable in face to face research (Opdenakker, 2006). This critical awareness and peer-coding of transcripts of recorded interviews goes some way in addressing these limitations.
According to Berry, Loughran, Smith and Lindsay, teachers’ knowledge of practice is largely tacit in that there are certain features of teaching, for example, “ the reasons for approaching teaching in a particular way” and “ways of recognising and responding to student learning difficulties” (2009, p.576) that are not generally found in teacher-talk about teaching and learning. A similar view is expressed by Kagan (1990), referring to teacher cognitions when she says that these are sometimes held unconsciously and that teachers often do not have the language by which to describe them. These features are made explicit to the teacher and researcher only when classroom practice is more closely interrogated. This implies that teacher rhetoric of practical work may not be a true reflection of what happens in practice. Citing Crossley and Vulliamy, Abrahams and Millar (2008) argue that neither questionaire-
based surveys nor studies based solely on interviews, are likely to accurately capture the essence of practical work as it unfolds in its natural setting, since it is more likely ‘to reproduce existent rhetoric”(ibid., p.1950). They recommend the observation of actual practices followed by a post-lesson interview with the teacher based on the belief that teachers’ responses are less likely to be rhetorical, knowing that the researcher had observed the lesson.
A description and rationale for using each of the data sources selected for this single case are outlined below.
1. Pre-lesson teacher interview
This interview aimed to explore the learning objectives the teacher hoped to achieve, the difficulties they anticipate and how their knowledge of the learners and context would influence their decisions related to the teaching of the topic. It was be a semi- structured interview (Bogdan & Bilken, 1992) where the guiding questions were informed by the prompts used by Loughran et al. (2001) in order to construct the content representations (CoRe) as a way of portraying teachers’ PCK. (see interview questions in Appendix B)
2. Lesson observation
As argued above, teacher rhetoric alone is unlikely to reflect the reality of a teacher’s practice and since certain components of teacher knowledge are only revealed in their practice, lesson observation is an essential data collection strategy. The main lesson and any other lessons during which instructions directly related to the proposed practical actvity were given, and during which any work started during the main lesson was completed, were observed. A series of eight lessons, of which five involved practical work. were video-recorded.
3. Post-lesson teacher interview
During this interview the teacher was asked to reflect on the lesson in general and based on excerpts from the video recording of the lesson, the researcher guided the teacher through a deeper reflection on certain aspects of the lesson. (see interview questions in Appendix C)
4. General practical work teacher interview
This interview explored the teacher’s perceptions of practical work, the learning objectives they hoped to achieve, the difficulties they anticipated and how their
knowledge of the learners and context would influence their decisions related to practical work in general. (see interview questions in Appendix D)
5. Learner interview
A group of five learners was interviewed two weeks after the eight lesson observations. In this interview learners were asked to reflect on what they learned in the practical lessons included in this series of lessons. (see interview questions in Appendix E)
6. Other data sources
Samples of learner work and learning material used during the lesson were used as evidence of teacher knowledge related to, for example, assessment and purposes for doing practical work.
A number of instruments have been developed to measure teachers’ knowledge. For example Mavhunga and Rollnick (2013) developed the pencil and paper content knowledge test and PCK test for chemical equilibrium; Ndlovu (2014) developed the topic specific pedagogical content knowledge (TSPCK) test and Phelps and Schilling (2004) developed survey instruments to measure content knowledge for teaching reading. Loughran et al. (2001) used CoRes and PaP-eRs to portray teachers’ PCK. Such instruments have not been developed to measure teachers’ knowledge for practical work and even if they were, they would not fit the purpose of this study, since the intention is to describe, and not measure, teacher knowledge.