other teachers should be called in to give their opinion on the teacher attempting to arm themselves, that the teachers students should be interviewed to insure that they are stable,

also think that the identities of the teachers that are armed ... should be confidential,

Be realistic: you can only have one of these things. If you're interviewing that many other people about any teacher who asks for a gun, word will get out.

Also, when we need people to be effective with a firearm under pressure, we give them intense training. Think of what police go through. Are you putting teachers through that? When? What if they wash out? Who is paying for it? If you don't (and even if you do) and they lose their head and their aim is crap when the time comes, do you know who is far more likely to be hit than the lone gunman? Any of the other 32 children in the room. Now we have a state actor shooting an innocent civilian. That would go over well.