The notion that putting a cop in every school is better than arming teachers is ludicrous. Yes, you need trained individuals, of course you do. But, a teacher can be trained to handle a gun just as well as a police officer can. And they're already there, you don't have to pay a person for being there. And worst of all, if that police officer is wearing a uniform, he's simply the first person a school shooter guns down. The shooter wouldn't even need a gun to get started, he'd just need a kitchen knife or a claw hammer to take down the cop, and then run amuck with his gun. The advantage of arming teachers and staff is that (1) they conceal their weapons; no one knows who they are except those who need to know. (2) There's more than one per school, so a would-be shooter faces multiple adversaries. (3) They're already there, you just pay them a little extra because they have to wear holstered firearms (something compact but potent like a Glock 19 or SIG M18) and soft body armor. You could put three in a school for less than 50% the price of one cop, and that includes rigorous annual training and more shooting practice than most police are required to do.