Guns, Schools, teachers, what else? Who's fault is it?

I think most of the problems lie with the parents.They think their kids do no wrong and let them get away with murder (figuratively speaking). They are let run wild and have no responsibilities to speak of. The teacher arrested sounds like a good person, but why did he have the weapon locked up at school? It was unloaded, even if he had to use it, heaven forbid! There are some teachers, though few and far between that I know of, that harass certain students. My oldest grandson was a victim, although he just let it slide. This person had no use for "jocks" as he called them, and he took it out on my grandson. Every time he turned around, this teacher was sending him to the office for something. It got to where the principal would laugh about it when he saw him coming and wanted to know what the teacher had done this time. My grandson was a very easy going boy, friends with everyone, even the teachers and principal, but this one teacher didn't like him for some reason. The principal finally had a talk with the teacher, and his harassment stopped.