In the history of stupid ideas, this one is Olympic class. Giving guns to untrained teachers is going to cause a lot more problems than it solves. Some of them WILL fall into the wrong hands. And when the cops arrive, how do they tell who the shooter is? But when one conforms the facts to fit one's ideology, it sounds perfectly reasonable.
With all the other crap that teachers have to put up with, I don't want live weapons in the classroom. This is not the time to pile extra responsibilities on teachers. In Omaha over 20% of teachers are not returning in the fall. Arming teachers will only drive more of them to seek other jobs. And I support them 110% to finding a job where they are supported and appreciated.