I'm kind of surprised to hear that a gunshow could even be held on school grounds. I think the law Bill Clinton signed prohibiting guns within 1000 feet of a school has never been repealed.
Many people don't believe it when I tell them I took a gun to school twice a week. But of course, the school would loan you a gun if you didn't have your own. You could bring your own ammo or buy it from the school at a discount. We had an indoor range and a rifle club and team. And no school shootings.
Seems that worked better than the zero tolerance policies in effect now.