When it comes to bullying in school, well...
My thoughts on it are simple: Get the almost-always-useless faculty to, you know, ACTUALLY FREAKING DO SOMETHING.
When I was in school, I was always baffled by that. Absolutely baffled. The bullying was OBVIOUS despite it not being the physical "steal your lunch money" sort. And I dont mean " obvious when it was happening to me". I mean "when it was happening anywhere". I could watch others being pushed around in very obvious ways, FREQUENTLY, yet the often braindead teachers and other faculty were so airheaded that they seemed to genuinely not notice (even during the times when it literally happened in the same very small room as them; it was actually pretty darned rare for bullies to have a chance to do it WITHOUT faculty around in that school). And this wasnt like, subtle stuff either, the bullies were not bright enough for that. It was pretty blatant. But I dont remember even one time when those useless oafs actually did their bloody job by intervening. No, no... I do remember ONE time where the faculty intervened. One. But that was because I *forced* them to do so... they wouldnt have otherwise.
Getting teachers and faculty that arent dumber than stumps is the first step, as far as I see it.
Unless things have changed since I was in school. Perhaps stealth bullying is a thing now, with ninjas pulling victims into the shadows to shove them around, I have no idea.
Now, as for stuff like cyber-bullying... that one is on the PARENTS to not be utter useless morons. CONTROL YOUR FREAKING KIDS WHEN THEY'RE ONLINE! Pay some bloody attention to what they're doing and what's happening with them. If they've got a social account? Watch it yourself! If they dont like that? TOO BAD!
You get those two things working in a less sucktastic way.... teachers and parents... and ALOT of trouble will vanish, because it wont have a chance to start without bullies getting in trouble instantly. Good luck making that actually happen though. People are dumb.
Now, that's all with traditional bullying, which was and is still very frequent. When it comes to the idea of exclusion, well... heck if I know. I hated everyone in schoolc anyway, so I refused to join any groups. I still think that way today.