I actually don't think any level of bullying is tolerable in any circumstances and you have to wonder about anyone who feels the need to engage in it.
Thankfully, there wasn't a whole lot of this kind of thing in my school system when I grew up. But I do remember in 8th grade or so when one of the big athletic kids picked on a nerdy guy with glasses and a pocket protector once too often. The nerdy guy bashed him over the head with a loaded cafeteria tray, and the big guy was led away bleeding from his ear. It was a proud moment.
I understand that school systems are afraid to take certain kinds of actions because they fear any kid's parents on any side of the equation might sue them at any time. But they better work out a viable response. I'd be in favor of suing school systems for inaction.