This fact sheet provides a list of "lessons learned" to assist schools in better preparing for a crisis event. The list was compiled by the Centers for Disease Control and Prevention and the U.S. Department of Education specifically to assist schools in preparing for a terrorist attack. The lessons can help schools better identify appropriate actions for school personnel to take in the event of a biological, chemical, or radiological attack and assist in preparing school emergency response plans. [Fact sheet produced by the School Violence Resource Center.]