The public school classroom that is. And there is only so much that teachers can do. Kids? They walk in with the attitudes that are- by-and-large - gotten from their environment at home for good or ill. Changing that? Oh. A bully might modify his/her behavior slightly at school. But if there isn't anything to make that change 'real' at home, it's just window dressing, nothing more. Once that kid is out the door everything changes. Without a great deal of effort, the behavior reverts to it;s default setting.
Some bully for the sport of it. Others because they are themselves bullied. While others bully because they are in pain- a lot of pain, and it gives them the sense of being able to control their feelings. Trouble is, it just adds fuel to the fire. How to stop? That takes skill. And more than what most schools can provide.
Kids are a reflection of what is going on at home. That's what I learned during my time teaching. And there is no way around that. Gets parents on board, that is, if they aren't drugging, boozing or zoning out, and all things are possible.
Too bad parents don't have to attend with their kids.
Be the love you seek.