Some are proactive in trying to prevent the development of violent behaviors, whereas others are reactive.
Certain programs focus on skill building, whereas others rely on the deterrent value of punishment. "Early Predictors of Violence." American Journal of Public Health, 90, 566-572.
According to 2001 polls, more than 50 percent of parents with children in grades K-12 and 75 percent of secondary school students now think that a school shooting could occur in their community.
Schools are taking a variety of measures to improve school safety.
 Violence is most common in large schools, and middle school students are the most likely targets of violent behavior. "The Relation Between Values and Social Competence in Early Adolescence." Developmental Psychology, 25, 458-464.
 According to a joint report of the Departments of Education and Justice,  violent crime overall has declined since the early and mid-1990s. For example, the percentage of students who reported being victims of crime at school decreased from 10 percent in 1995 to 8 percent in 1999. Also, even in light of the 5 percent decrease in weapon carrying between 19,  7-8 percent of students in 9th to 12th grade continue to report having been threatened or injured with a weapon on school property. What is more, official statistics are often lower than the actual rates of violent behavior because of biases in reporting. Childhood bullying predicts person-oriented crime in young adulthood.Thus, bullying is one precursor of more extreme forms of hostility. In addition, a small but potentially volatile group of youth not only perceive themselves as the victims of peer taunting and ridicule, but are also aggressive themselves. Although more research is needed to identify the conditions under which victims of bullying are most likely to lash out, it is clear that hostilities among school children increase the risk for subsequent violence. Faced with intense public pressure, school administrators are taking action and implementing programs designed to curb school violence. An analysis of the key components of various approaches in terms of their potential positive and negative effects can assist in the selection of policies, programs, and procedures while we wait for evaluations to be conducted. FACTS ABOUT SCHOOL VIOLENCE School violence is not confined to urban schools; it is also prevalent in suburban schools. Physical Surveillance Among the most common physical surveillance measures currently used in schools are weapons deterrence and the use of campus security and police officers. School Security Is at Top of Agenda." Los Angeles Times, A1. These strategies are aimed at preventing the most extreme forms of violence. Although bullying is far more prevalent than violence that involves weapons,  one primary goal of improved physical surveillance measures is to prevent youth from bringing weapons to school. "In the Classroom: Metal Detectors and a Search for Peace of Mind." Los Angeles Times, B2. Some approaches involve the entire school and sometimes even parents or the community at large; others are designed for students identified as "at risk." Finally, certain approaches focus on resolving incidents rather than identifying problem students. Hence, school-based violence prevention efforts are based on drastically different sets of assumptions about what works.