This study introduces a social context model within which peer acceptances of prosocial-leadership, aggression, and social withdrawal were examined as functions of the contextual norms of these behaviors. The major postulate of the model is that the extent to which a behavior permeates a social context facilitates peer acceptance of the behavior. Specific hypotheses with respect to classroom and gender as different social contexts were formulated and supported when tested in a sample of 4,650 Chinese middle school students from 82 classes. The discussion emphasizes the theoretical as well as the methodological need for alternative conceptualizations of peer relations that reflect both individual differences and contextual variations.