NTJ! Some of these comments are sad!! If he forgets them the consequences he faces at school will be a lesson learned. He is 13 and more than old enough. Just think back to what a 13 year old male had to do a long time ago to keep life running for his family. Thankfully it's not required anymore but definitely a sign that as parents our kids will only meet the expectations we set and the bars are often times set way too low!!!
NTJ but don't bully his parents because you are angry. Sit the parents down and have a conversation about the bullying and offer support and help. It can be very difficult to manage a child with bad behavior and can make a parent feel very alone and disconnected while trying to find something that works.