This study aimed to understand the extent to which parent involvement, community involvement, and schoolwide violence-prevention initiatives reduced school violence, considering school racial/ethnic compositions and crime levels of school locations. We used school-level data collected during the 2009–2010 school year, covering elementary schools (n = 684), middle schools (n = 909), and high schools (n = 948). Results revealed that higher levels of parent involvement in school activities were associated with fewer incidents of school violence for elementary and middle schools, whereas more community involvement in school efforts predicted more school violence. Staff training and student-oriented prevention programs did not relate with school violence in primary and secondary schools. Additionally, parent involvement served as a protective factor for schools with high levels of racial/ethnic minority composition and/or located in neighborhoods with high crime levels. Differences across school levels were taken into consideration when drawing conclusions.