Learning to Design Geometer’s Sketchpad Activities for Teaching Mathematics through Lesson Study

This study aimed to develop pre-service teachers’ skills and confidence to design Geometer’s Sketchpad (GSP) activities for teaching mathematics through Lesson Study (LS). The researcher employed a case study research design and the participants comprised 26 pre-service secondary teachers who enrolled in the mathematics teaching methods course in a Malaysian public university. Thirteen LS groups each comprising 2 participants were set up in two tutorial groups. Qualitative data were collected for each LS group through observations, written lesson plans, reflections and GSP activities. This paper discusses the changes in the GSP activities of one of the LS groups for teaching the sum of the interior angles of a polygon in the first, second and third lessons. The findings indicate that the participants of this LS group showed gradual improvement in their skills and confidence to design GSP activities for teaching the topic after engaging in LS.