Abstract
In the current mathematics education reform efforts teachers are challenged to develop discourse communities where students learn to construct and evaluate arguments used in
mathematical reasoning. The challenge for teachers is to know what actions to take to establish such discourse. In this study I investigated the actions a teacher took to establish the discourse of inquiry and challenge within a community of diverse learners. I report on the way in which the teacher shifted back and forth among a range of roles, as a facilitator of the discourse, as a participant in the discourse and as a commentator about the discourse.