Participating in classroom mathematical practices

In this article, we describe a methodology for analyzing the collective lea rning of the classroom community in terms of the evolution of classroom mat hematical practices. To develop the rationale for this approach, we first g round the discussion in our work as mathematics educators who conduct class room-based design research. We then present a sample analysis taken from a Ist-grade classroom teaching experiment that focused on linear measurement to illustrate how we coordinate a social perspective on communal practices with a psychological perspective on individual students' diverse ways of re asoning as they participate in those practices. In the concluding sections of the article, we frame the sample analysis as a paradigm case in which to clarify aspects of the methodology and consider its usefulness for design research.