Objectives: To examine cross-sectional and 2-year longitudinal associations between school victimization and aggression among middle and high school students. Drawing on resilience theory, family and school connectedness were examined as compensatory or protective factors. Method: We sampled 373 students (Grades 7–10, 54% girls, 53% White/Caucasian, 26% Hispanic/Latino, and 56% economically disadvantaged), who completed up to 3 annual surveys. Results: Aggression declined over the 3 waves. Victimization predicted higher initial levels of and steeper decline in aggression. Family connectedness was protective; baseline aggression was lower and declined more steeply for youth who reported more family connectedness. School connectedness played a complex role, potentially contributing to students’ vulnerability over time. Conclusions: The steeper declines in aggression among victimized youth suggest a resilience process. High family connectedness and school belonging were linked to lower level of aggression regardless of victimization. Efforts to provide family support may be effective in reducing risk for aggression among victimized youth. Promoting students’ sense of school belonging may compensate for negative effects of victimization on aggression in the short term; however, broader efforts directed at establishing a safe and supportive school climate and setting social norms that discourage school violence may be necessary to reduce the incidence of victimization and subsequent aggressive behavior. (PsycINFO Database Record (c) 2016 APA, all rights reserved)