Your such a gangster.
It's a position that many support.
You hold the teachers accountable - if they drop/lose/misuse that weapon, they see prison. You require background checks, training, licensing, and above all, absolute concealment. If and when you have a situation where a student, local madman, or terrorist decides to start some ruckus at a school, you have any number of teachers (who know the lay of the school and who belongs way better than any cop who will show up 90 minutes later) showing up quickly.
It's a reasonable solution. Wouldn't have to be a huge deal either.