There are different types of evidence that reflect students' thinking in classroom interactions. Student discourse, gestures, actions can be shown among these. The aim of the current study is to reveal the skills of secondary mathematics teachers with different professional experiences to notice different types of evidence of student thinking. For this aim, the study was designed within the context of a case study, one of the qualitative research methods. The data of the study were obtained through video-based interviews with five secondary mathematics teachers. Six video episodes containing different types of evidence for video-based interviews were shown to teachers. In the interviews, targeted questions were asked to reveal what types of evidence the participating teachers took into account in the videos they watched, how they interpret these types of evidence, and what kind of instructional decisions they suggested. The types of evidence that teachers noticed in the videos and how they made sense of the evidence were analyzed qualitatively. Various findings have been revealed depending on the different professional experiences of the teachers. First, experienced (5 years and above) teachers paid more attention to the types of verbal evidence of student thinking. Student statements and questions were more visible to experienced teachers, especially among oral evidence. Second, the evidence-based comments described by the experienced teachers were aimed at drawing more conclusions. However, it is noteworthy that teachers who make inferences based on student's cognitive thinking also attend postgraduate education or professional experience courses. Third, the instructional decisions of experienced teachers who attended postgraduate education and professional experience courses, based on student thinking, were mostly related to specific mathematical subjects.
A Professional Experience Learning Community for Pre-service Secondary Mathematics Teachers
