I totally agree with Michael Moore and one guy who comments on the video also states an important fact: where are the fathers? You never see the fathers of these hay-wire kids. How are they supposed to grow up being responsible, respectful adults, when they're just scared of everything and respond the only way they know: eliminate what scares you.

As to bullying, it's as old as humanity, but the one character that is sorely missing in schools now is that natural-born leader, the noble, protective, prestigeous (or bigger, or smarter, or older) classmate that stands up for the weak and puts the bully in his place. (Something like the character of James Steerforth in David Copperfield).
Kids now gang up to beat up one single mate, something unheard of in my days, while the rest look on and don't dare step in, even if the victim is a girl.