This article examines whether and in what ways curricular approaches can be helpful in building positive interethnic relations in a large, ethnically diverse high school. Through this case study of curricular reform, the author documents four curricular approaches teacher leaders used to explicitly address issues of race and ethnicity and explores the impact of these approaches on student learning. By tracing the process of curricular change, the case illuminates how teacher leaders and administrators created the conditions for these curricular reforms to be sustainable.