We had a similar incident, where my son was being beaten up on the bus.
I spoke with his principal twice and was told that the issue would be resolved.
When it happened again, I arranged a meeting with the principal, the bus driver, myself, and my son.
In the presence of the principal and the bus driver, I told my son that the next time someone started to bully him he was to double up his fist and flatten every nose within reach.
The principal threatened expulsion if he struck another kid. I simply replied that if he got expelled, I would take a few days off work, and we would take a trip to Six Flags, or some other fun thing.
The moral of my story is, that sometimes you have to fight back.
You would also be interested to know that the next day the 2 kids who we had complained about repeatedly were removed from the bus.
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