Times have really changed. When I was in high school in the 80s, nearly every guy I knew -- along with all the male teachers -- carried a pocket knife. They came in darn handy if you needed something and especially when you couldn't locate a custodian. We didn't think a thing about it. It was just a matter of course. I don't *ever* remember one being brought out as a weapon in a fight.
Nowadays, if you walk across the school parking lot with a folding nail file in your pocket, it's grounds for expulsion.