Boundary objects in mathematics education and their role across communities of teachers and researchers in interaction.

Studying interactions across communities of mathematics teachers and educational researchers in professional development poses theoretical challenges. The authors suggest that it may be productive to view such encounters as the meetings of two professional communities that have different, possibly conflicting perspectives on the theory and practice of mathematics education. Drawing on the notions of boundary objects and boundary-crossing, the authors propose a framework for how teachers and researchers may learn from and with each other through joint work on common objects, through which they can explicate, reflect upon and modify their perspectives. Through the analysis of three educational projects from different countries - Italy, France and Israel - the authors describe ways in which the structure of boundary objects supports various aspects of dialogical learning, thus providing an initial frame for the proposed theoretical constructs.