Talking the talk: A longitudinal case study of the development of early career science teachers’ knowledge of the nature and purposes of classroom talk.

The complexity of teacher professional knowledge is well established in a range of models of professional knowledge (Shulman, 1986; Engeström, 1987; Eraut, 2014) and a number of studies have examined models of science classroom talk (Mortimer and Scott, 2003; Viiri and Saari, 2006; Lehesvuori et al., 2013). However, research that tries to use models of classroom talk to develop classroom practice has identified challenges in the complexity of developing teacher knowledge in this area (Viiri and Saari, 2006; Lehesvuori et al., 2011; Chen et al., 2016) .This study uses a longitudinal case study approach to examine the development of early career teachers’ understanding of the nature and purposes of science classroom talk. Seven case study teachers were interviewed over a three-year period from their initial teacher training until the end of their second year of employment. Alternate semi-structured and unstructured interviews explored the teachers’ views of how and why they used talk in their classrooms. The interviews present a complexity of interaction between training experiences, individual identities and the multiple communities of practice in which the teachers work. These interactions create tensions and conflicts for the case study teachers as they develop their understanding of the nature and role of classroom talk. The experiences of the case study teachers suggest that for research on classroom talk to influence teachers’ practice there needs to be a recognition of the important influence of teachers’ own identity and ideas about learning. A model of science classroom talk is developed that integrates theoretical frameworks for science classroom talk with insights into how early career teachers think about classroom talk in their practice. The findings also provide insight into the complexity of teacher knowledge in an area of practice that is both fundamental to the role of a teacher and underdeveloped as an area of professional development.