We had ongoing issues with one particular boy in my son's class for the first few years of school, and you have to be extremely proactive in advocating to get any type of help, IME. I have a pretty no nonsense approach, I never yell, I stay calm, but I can be very firm too. I included the principal in all complaints to the teacher (in order to hold the school accountable and also to have everything documented), and would go to the school and meet with the principal and/or teacher on a regular basis when we were in the thick of it. We also have a counsellor at the school so my son was meeting with them as often as he felt necessary, and they were very instrumental in helping give him tools to deal with the bullying/intimidation/physical aggression/stress. Basically the idea was to empower him, despite being MUCH smaller and a full year younger than the child who was bullying him. The parent of the other child was also called in multiple times to meet with the principal and teacher, and there was also an incident during soccer practice outside of school time that required meeting with the coach. She became very aggressive towards me, was in complete denial about the issue, lied to other parents about me, and tried to bully me (apple doesn't fall far from the tree!!) into making my son have play dates with her son because she said the reason her son was being aggressive is that he was jealous of my son playing with other kids and her son didn't have any friends. My son set some firm boundaries with the help of the school counsellor and decided he wanted to distance himself from the classmate, so we supported him in that. If he had decided he wanted to have a friendship with the boy, we would have done our best to support him in that too. At no point did we interfere directly between the two boys, and we are happy to say it did resolve eventually and he became much more confident in the process. They are still in the same class, and I check in regularly to see how things are going... he has said for the last few years that they have come to an understanding where they are civil to each other, but will never be close as far as he's concerned. Wishing you all the best, and please use any resources available to you in your school system. It really does help.