If the teachers won't do anything to help, you can file a police report. For junior high kids, that is almost an impossibility if they are on the receiving end of the bully stuff. Again, don't mistake arrogance for high self-esteem. Many studies have shown bullies have a low self-esteem. Again, their main goal is to control.
All cases are individual and as unique as people are.
But yes, many bully kids also have bully parents. Most of the time you don't know, or you won't admit, that you are a bully. My parents talked to the bully's parents, and the bullies even bullied me more. They need to keep an eye on situations like that. Again, if they don't, people need to file police reports.