We summarize current data and understanding about the prevalence of gun violence at schools and risk of rampage school shootings. Following that comes a discussion of gun availability among youth and strategies and practices in the United States and abroad that have been implemented to limit access to firearms for minors. Next, we review the current evidence for arming school teachers, a strategy that could also increase the number of firearms in schools. We then focus on three specific strategies that schools have implemented to reduce school shootings and improve school safety: (a) addressing the role of mental health in school shootings and violence perpetration; (b) implementing multidisciplinary threat assessment protocols; and (c) target hardening and utilizing school resource officers. Based on available evidence, a public health approach to addressing firearm violence in schools is the most effective way to prevent school shootings, even if these effects are indirect through improvements in student social competence and positive school climate. Finally, we offer some recommendations for future practice, policy and research.