Adolescents, 12 to 18 years (N = 962), were asked how often they worried about, heard about, witnessed, were victimized by, and committed aggression at or near their schools. Social, moderate physical, and violent aggression were assessed. Females heard, worried, and witnessed more social aggression than males, but both were victims and/or perpetrators of social aggression. With increasing age, hearing about moderate physical aggression increased (p = .001), but being victimized decreased (p = .01). Committing moderate physical aggression was predicted by witnessing (p less than .001) and being victimized (p less than .001) by moderate physical aggression. Committing violent aggression was also predicted by witnessing (p less than .001) and being victimized by violent aggression (p less than .001). Practical implications for school systems are that assessments could be used to measure the occurrence of different types of aggression in the schools and focus interventions on the aggression types that are most problematic. (Published Abstract)