Yes, I would. If I turned on the news and saw that a gunman was in the same school my child was in, I would prefer the child be in a classroom with an armed teacher rather than an unarmed teacher. By the way, I believe the people chosen for being armed in schools will be vetted and trained.

By whom?
The majority of my school days were taught by veterans and tough, stern old gals with only the very occasional liberal flake for variety. Not sure if that's the case any longer.
I agree with Muss in that anyone qualified to carry should be allowed and focus on securing classrooms as a refuge.
My father would have wept to see campuses become prison camps yet he would have ripped the head off anyone attempting harm to his students.