How should kids react in a school shooting?

[Husar]

Bullet proof steel doors and bullet proof windows, costs a lot to buy burt they cannot come in anymore, unless they move on to school shootings with RPGs. Preferably all those doors can be locked remotely by the principal and/or the security personnel, then add some vidya cameras, machine gun turrets and flame thrower barriers, a bunch of marines with an APC as a rapid deploament security force and your kids are finally secure. Expect a little rise in schooling costs or taxes though.

edit: Alternatively you could try a MAD scenario and put a tactical nuke into the cellar of the school.