This is not CNN:
Mind you, I'm not advocating the "forced" arming of teachers at schools. But since my father was a high school teacher for many years, and a very active one, I know that if financial incentives were put in place to encourage some number of teachers at schools to train with and carry guns, that some would accept the offer willingly. Many of the teachers I knew growing up were WWII vets, and not exactly shrinking violets.
No single action can prevent school shootings. but raising the chance that a shooter would meet armed resistance from the outset would be one measure that might make a difference.
Wombat-socho has "Rule 5 Sunday: Larger Than Life" up and running on time and within budget at The Other McCain.