I'm not tall at all, and going through school I was easily one of the five shortest kids in any of my grades. I was fairly stocky, but short. I was pretty popular through school, but certainly got made fun of for being short when I was in grades 2-5 or so. Well, I didn't really take shit from anyone, basically because I was always told that you HAVE to stand up for yourself, and got in a fair number of fights when I was younger. Pretty much the same story, where I'd get in shit, although usually the other kid would too. My parents went to bat for me every time, but none of these were all that serious, and most of these altercations were with people I'd be on relatively good terms with the rest of my school career. Kids are going to fight because they fuck around with each other all day and eventually tempers ARE going to flair. I've been on both sides of the situation you're talking about, and although always very suprised at the time when someone snapped, I'd totally understand it when everything was said and done.
I know what the teachers and administrators are trying to do, but it doesn't really work out. The problem with the principle of trying to teach that physical violence is never the answer is that it actually is the answer a lot of times. If you run your mouth all day you're going to get hit eventually. I've hit people for doing it and I've been hit for doing it. The problem with indiscriminately punishing kids for throwing a punch is that it creates an attitude like the one that reporter had on the clip posted here, "I can do anything, don't touch me". No, sometimes you need to punch someone the fuck out. Not just because what they're doing is bothering you - but because that's the only way to get them to stop doing whatever the fuck it is.
It probably won't stop and you just have to keep on going to bat.