The "urban" mathematics classroom has become an increasingly polarized site, one where many middle-class White teachers attempt to bridge the divide between themselves and their relatively economically disadvantaged, non-White students. With its mania for high-stakes testing, current education policy has intensified the importance of…

Background/Context: Research shows that teachers' understandings of students, subject, and teaching influence their classroom practice. Additionally, teachers' colleagues have a role in shaping individuals' approaches to teaching and their responses to reform. Focus of Study: To understand how interactions with colleagues support teachers'…