Abstract:
Lesson Study (LS) is a teacher-led and practice-situated professional development (PD) model that teachers use to improve their teaching and to foster learners’ mathematical thinking. There are different variants of LS globally. The unique feature of South Africa’s LS variant is at the diagnostic assessment/analysis stage. Diagnostic assessment/analysis is credited for assisting teachers to gain an in-depth understanding of learners' misconceptions about a particular topic or concept. The purpose of this qualitative case study, based on interpretive paradigm, was to examine mathematics teachers' diagnostic assessment practices when implementing LS. I addressed the following main research question: How do mathematics teachers use the LS cycle to identify learners’ misconceptions in mathematics? Data was collected through observations and interviews from a team of mathematics teachers participating in in-school LS. I used two theoretical lenses: the situated learning theory (SLT) in which LS is rooted, and the taxonomy of diagnostic competences (Fischer, Kollar, Ufer, Sodian, Hussmann, Pekrun, R. & Eberle, 2014). Four key findings were revealed: firstly, teachers conducted a comprehensive diagnostic analysis to identify the problem and generating possible causes of the problem; secondly, in their attempt to create artefacts (instructional activities) teachers did not collaboratively interrogate them to ensure that they were purposeful; thirdly, although the process of generating evidence through lesson presentation was done appropriately, teachers were restricted by the activities and questions that were not purposeful; and lastly, instead of focusing mainly on evaluating evidence against their assumptions during the reflection session, teachers focused on the challenges and the affordances of LS. Essentially, there is a need for policy makers and teacher development institutions to empower teachers on diagnostic assessment, thereby institutionalising it as a mathematics classroom culture.