Classroom peer factors were examined for their role in African American and White early adolescents' sense of belonging in mathematics classrooms. After controlling for fall sense of classroom belonging, spring sense of belonging was greater when teens perceived a more supportive peer context, minimal emotional risk in participating, and when they were recognized by peers as being strong math tutors. Additionally, naturally occurring peer groups were differentiated by sense of belonging of members; peer networks that began the year below average in sense of belonging became more alienated during the course of the year, whereas networks above average in belonging stayed at fall levels. The results are interpreted in relation to the benefits that specific peer relations offer aspects of adjustment such as belonging.