This article examines how students and teachers at an urban public high school embodied and understood various social categories of difference. Although ascriptions and experiences of racial and gender identities varied, these identities were often viewed as biological in origin and static in nature. The complexities and contradictions evident in the everyday conversations about difference at the school might serve as effective starting points for discussions about the social construction of difference. [race and gender, everyday discourse about difference, high school, race as a biological category] Karen Levy was reviewing the week's vocabulary words in her 9th grade English class. To explain the word "adherent," Mrs. Levy asked if one could be an adherent of a racial group. Before the students answered, Mrs. Levy asked the students to raise their hands if they were Catholic, Jewish, and so on. Mrs. Levy then said that there are some things one can choose and others that one can't. Race and ethnicity, she said, were identities one could not choose, while religious and political affiliations were chosen identities. Tyler, an African American male student, said, "You can choose