I agree that they are going over board. It's a serious case of CYA by the people in charge. I mean really, what are the chances? And if you close down the school, all the kids go to the mall where they are more out in the open.
What I can't figure out is, why don't the communities start a neighborhood watch program? At least until the sniper is off the streets. It wouldn't be that hard to put one or two people on every street corner keeping an eye out for suspicious activity. If it were happening in my community I would try and organize such a thing. Hell, you could probably even get plenty of out of state volunteers to help.