Currently the law in Pennsylvania about guns in primary and secondary schools is a grey area. Having firearms in schools is generally prohibited, except with an exception for guns possessed for lawful purposes. Given Heller, self-defense is a lawful purposes, perhaps the most lawful purpose, for possessing a firearm.
But just because that’s what you or I think doesn’t mean that’s how prosecutors or judges are going to see it. Looks like a School Board member almost got busted for having a gun in a school, but the Bucks County District Attorney’s office are going to decline charges. The grey area will live. I’d like to see this issue decided one way or another, though I certainly wouldn’t volunteer to be that case, and hope no one else will either. Two things likely helped this guy. One is that he’s a public official, and while it’s wrong, public officials tend to not want to prosecute other public officials. Two if you’re a DA going to go forward with a precedent setting case, you’d likely want the circumstances to be as horrible as possible, like some dipshit who carried in a school and left it in a bathroom (and wasn’t a cop), or who had a negligent discharge (and wasn’t a cop) What you have with our school statute is a way a sympathetic judge or jury could screw your chance of getting a conviction, and I don’t think prosecutors usually like taking that kind of chance.