I spent about an hour working on this today. There's a federal limit apparently, but most states have their own rule:
State-by-State Safe, Orderly, and Drug-Free Schools
And it gets a lot worse. As 7xstall points out, it's not just schools you have to be wary of. The zones can also be based off of things such as bus stops, bus routes, school bus stops, church daycare/private school.
This is putting a major fucking kink in my plans. On the other hand, I'm glad to know now before I buy a house in a neighborhood that will be hard as hell to sell in.
As for the firearms....I guess I'm going to have to buy my buddy a gun safe and stash my shit over at his place. I love guns, but I'm not going to play that bullshit.