What happens to children inside and on the way to and from school reflects what is happening in surrounding communities. Thus, understanding the problem of guns and gun violence in schools requires an understanding of the problem in its larger societal context. Both official statistics and varied research literature have examined the incidence and impacts of firearm injuries and violence on school-age children and the levels of exposure and access to firearms by children. The data reveal that death and injury from firearm violence are a much less common problem in and around schools than in the neighborhoods in which children live. Nevertheless, the impact of even one such death or injury can extend far beyond those directly involved, through psychological trauma to friends, acquaintances, and witnesses, and by severely disrupting the learning setting. A research-based process to determining effective approaches to prevention begins with defining the problem and progresses to identifying risk factors and causes, developing and implementing interventions, and evaluating intervention programs. Prevention strategies include controlling access to firearms, changing how firearms are used, and reducing the lethality of firearms and ammunition. The current knowledge base suggests that an effective framework for local and national progress on this issue includes establishing school-based surveillance systems for violent behavior, using science to guide action, and establishing a learn-as-we-go approach. Figures, tables, and 56 references (Author abstract modified)