Okay, so you say training required. So how fucking hard is it to have a plan and training tailored to the schools emergency plan? As of now the kids all huddle in a predetermined corner of a class, and are told to stay there no matter what. So if you know where this is to happen it is something that you know that the assailant does not. This is not just some bullet flying free for all, we are assuming proper training and planning in conjunction with the preexisting school emergency plan. OP, sorry but your post is dumb and lacks thought. It is the same "what if" argument that liberals use to say that guns are to dangerous for us common folk. Train, and execute to the best of your ability your school's plan and chances are a situation like you describe would not be likely, possible but not likely. Don't "what if"; answer those questions to yourself before you post something like this on a public forum.