AbstractExperiences with classmates can affect adolescents’ academic, emotional, and social development. The aim was to examine whether changes in classmates’ modeling and reinforcement, induced by an intervention, affected changes in adolescents’ perceived classroom peer context and whether these associations were moderated by dyadic mutuality. Questionnaires and observations were used in a sample of 7th Grade students (N = 152; M_age = 12.37; 53.8% boys). Generally, changes in classmates’ modeling and reinforcement were unrelated to adolescents’ perceived classroom peer context, except for classmates’ prosocial modeling. Increases in prosocial modeling were related to decreases in victimization, especially for dyads with high levels of mutuality. The results suggest that classmates’ prosocial modeling may be more important for the perceived classroom peer context than classmates’ deviant modeling.