Those who get beaten up for lack of mob mentality, learn by the experience and years later own the businesses which then hire the ditch diggers.
Those same people who get beaten up, eventually hold their own and authority figures who would prevent this process are just delaying it until the participants are older, out of the school system, and are ready to act the whole thing out with a gun. Children are a wonder to watch evolve. Our meddling in many cases just ruins the process.
In all cases I can think of, such situations eventually end up with both participants becoming friends. When you have been passionate enough as a child to split a lip, blacken an eye, and stood up to each other, it builds a mutual respect after the immediate emotion has wained. The school should start boxing classes. That would be more helpful than an army of school administrators and psychologists.