Abstract
The purpose of this study was to find answers to the following two questions: What happens when a teacher follows his students’ alternative ideas in his mathematics classroom? What is the limit of letting go in a problem solving process? A teacher with 15 years of mathematics teaching experience tried to modify his pedagogical practices towards an argument-based approach as part of a professional development project. This paper is a snapshot of a lesson selected from a number of videos recorded in his classroom when teaching “real numbers unit”. The data were analyzed using an observation matrix whose bases are creating dialogic interaction, controlling problem solving process and making connections. The results revealed that the teacher hesitated to let the students follow their own problem solving process and explain their mathematical understanding because of his “comfort zone” in traditional way of teaching. This type of hesitation in changing pedagogy blocks shifting from an algorithmic view of mathematics to the mathematics as a constructed action