This month a company in Spokane, Washington, plans to release "Shots Fired on Campus," an instructional DVD with strategies for preventing and surviving a gun rampage. About 50 colleges have ordered the video, and its creators expect to sell several hundred more this fall. Since the massacre at Virginia Tech last year, colleges everywhere have prepared for "active shooter" scenarios. As last February's fatal shootings at Northern Illinois University affirmed, however, even the most rapid police response may come too late for some people who first encounter a gunman. "Shots Fired," which includes interviews with law-enforcement experts, shows viewers how they might live through such a shooting ordeal by running, hiding, or barricading a door. It also depicts how, by spreading out and working together, a group of people might overpower and disarm a shooter.