Using classroom video-based instruments to characterise pre-service science teachers' incoming usable knowledge for teaching science

Background Effective science teaching requires a specialised body of knowledge. Researchers have recognised the importance of understanding the incoming knowledge that pre-service science teachers (PSTs) bring to their initial teacher education. However, although many studies have focused on PSTs' declarative knowledge or the knowledge that informs their lesson planning decisions, few have considered the knowledge that PSTs activate and use in contexts similar to authentic classroom situations. Purpose This study investigated the nature of PSTs' incoming usable knowledge for teaching science. Specifically, it utilised two video-based tasks, a video annotation task and an interactive video analysis task, to explore and characterise the nature of two forms of usable knowledge: knowledge that informs PSTs' analysis of classroom situations and knowledge that informs their in-the-moment instructional decision-making. Methods Fourteen PSTs attempted two video-based tasks at the beginning of a science major methods course. Their responses in the two tasks were analysed qualitatively to shed light on the two abovementioned forms of usable knowledge. Findings The PSTs readily identified the general pedagogical knowledge (PK) and topic-specific pedagogical content knowledge (PCK), but not the discipline-specific PCK displayed by the teacher shown in the videos. Second, the PSTs readily identified examples of students' non-cognitive engagement or content-generic thinking in the videos. The PSTs tended to describe rather than activate their knowledge of student understanding to interpret the examples of students' cognitive thinking identified in the videos. Third, the PSTs relied primarily on PK, not PCK, to suggest alternative instructional strategies/representations. Finally, the PSTs' responses were seldom connected with emergent student thinking; instead, PSTs relied on PK rather than PCK in their on-the-fly teaching decisions. Conclusion The study delineated two forms of PSTs' usable knowledge for teaching science and exemplified how video-based instruments can be used to systematically investigate teachers' usable knowledge for teaching science.