Let's say that (this isn't real k) you were banned from the hopscotch forum, right? So after that happened, one day you went to school and you do hopscotch at your school. Your teacher tells you it is required to have a forum account. Would they be allowed to have one or not?
I think you would still get one, unless if you got banned on your school account.
You should not be able to be suspended.
Usually teachers won't like you to be communicating with people you don't know on the forum.