Secondary science teachers' knowledge base when teaching science courses in and out of their area of certification

Abstract This study examined the similarities and differences in experienced secondary science teachers' planning, teaching, and reflecting on their teaching, when teaching in their science area of certification and when teaching in another science area. The study also focused on the influence of these teachers' content knowledge, pedagogical knowledge, and pedagogical content knowledge on their planning, teaching, and reflecting. Experienced teachers were observed and interviewed while teaching classes in their science area of certification, and in another science area they were teaching for the first or second time. Both similarities and differences in teaching were found in the two areas for all three teachers. For example, their planning and postlesson reflections were similar in both areas. In the interactive phase of teaching more differences were observed. Many aspects of their teaching resembled that of expert teachers in other studies. In the unfamiliar science area, the teachers sometimes acted like novice teachers. However, they were able to draw upon their pedagogical knowledge to provide a framework for their teaching in both science areas. Their wealth of pedagogical knowledge, and pedagogical content knowledge for general science topics, seemed to sustain them in whatever content they were teaching. Recommendations for further study and implications for teacher education are discussed.