Air Marshals carry firearms in secret on airplanes, why can't we allow select teachers to be trained in firearms use/safety, and have them be "undercover" in schools?
There are many people with past experience as police officers and military who teach, so why not enable them to carry firearms, as well?
It's dangerously naive to leave those who are to educate and protect our youth DEFENSELESS against madmen.
We cannot defeat evil by weakening the ability of the Good to defend themselves and others.
We don't need a "gun in every classroom," but we also can't expect that all we need is the "right" law, or another restriction or background check to stop harm from coming to our children.
Those who would do harm to our children might think twice if they know they will face unknown odds.