--- - |2 This study examines whether social‐emotional difficulties associated with higher body weight vary across schools as a function of the school's weight climate. Weight climate, characterized by weight‐policing, was assessed indirectly by examining how strongly self‐reported weight predicts victim reputation within 26 ethnically diverse middle schools. Social‐emotional indicators included self‐reported loneliness, school belonging, and self‐esteem. In schools with stronger weight‐policing at seventh grade, loneliness was intensified by eighth grade among both girls (n = 2,101) and boys (n = 1,985) with higher weight. Similar effects were found for low self‐esteem among girls. Additionally, boys—regardless of their weight—reported lower sense of belonging in schools with stronger weight‐policing. The study offers a new method to estimate school weight climate, and the findings provide insights for interventions. - Journal of Research on Adolescence, EarlyView.