Teachers should definitely be trained and allowed to carry guns (especially at schools with high crime rates). It's pretty much the same thing as arming air marshalls and pilots on planes. Teachers are the first line of defense against any potential perpetrators, whether they're students or outside criminals, who would shoot up our schools. Armed guards probably aren't going to be where the action is at first anyway. Give the teachers the power and save the 10 bucks an hour we're wasting on the security guards!