This is an ugly topic but thought I'd menton it anyway.

Your team should talk with local law enforcement about their reaction to a "shooting in progress", such as what happened at Columbine. If your local police force dosen't have a policy or prepared reaction to such an event they should. If they already do you need to know how to work with them in terms of communication and removing your students to a safe area.

BTW new studies have shown that in many of these types of situations the most effective first responses have been from armed citizens who arrived first, several have been school faculty. Food for thought. Mac