I'm certain we don't remember the expulsions: Normally the kids simply didn't return after the summer, and we concluded they must have moved away or whatnot. Kids aren't known for their in-depth perceptive powers and synthesis cognitive skills.
The military used to be a place where, if you had a behaviour disorder, you'd simply be thrown in a hole for six weeks, then be given duty clearing a minefield. Today, they simply discharge you.
I have a wealth of experience dealing with behaviour modification, using every technique you can imagine. There is no magic bullet, however, perscritive medication given by a psychiatrist (schools, teachers, etc cannot perscribe these) is ONE possible, and often very effective method. This is particularly useful in modern housholds where both parents are employed full time, and an exausting, time consuming regiem of behaviour modification is not possible.