I know teachers who are well qualified and damn good shots.
but that is not what they are paid for. Their job is to teach. I can shoot, hit my target under fire, and protect myself; unless I am receiving a salary for that, I'm not going to be doing that as part of my job.
@Trajan61 Since the 2nd amendment predicates a well regulated militia, every person that owns a military style rifle should be required as part of their service to stand guard at local schools on a rotating basis. They would be under the control of the governor, required to take mental and physical evaluations, train and prove proficiency. Can't or won't provide needed security, surrender your weapon.