This is an excellent point on why we DON'T allow backpacks in the classrooms where I teach. I know my sister, who adopted a meth baby who is now 9, checks his pack every morning before he leaves...not necessarily for weapons, but, to make sure he has all of his things. I'm just SO glad I don't have kids...I would lose my mind!
While, I'm sure, the kids had outside influences, the fact remains they brought the things to school with an intent...and it wasn't good! I have no idea what kind of background these kids came from and in the grand scheme of things, it doesn't matter, what does matter is that it happened. It speaks volumes of today's society.