Can we have an actual debate here instead of sarcastic comments? So far only a couple folks have said ANYTHING of worth about why we shouldn't have guns in school: cost prohibitive, and risk of the protector being mentally unstable.
The fact of the matter is that we do have armed security in banks. In airports. In stadium events. In some larger shopping malls. In government buildings. Even on some college campuses.
After a lot of violence in my high school, they started posting a police officer there, who would either be out in the parking lot, or by the front doors. While there has still been outbursts of violence there, it hasn't escalated to needing squads of police, and tear gas being deployed.
Why would you not want a trained armed security patrol or police officer on elementary or high school grounds?