I'm not a lawyer, but this seems like a clear violation of the Establishment Clause of the first amendment.

In my opinion, Every student can whatever flag they want at school, but the school should not be allowed to wave flags of theocratic nation states.

I would prefer they didn't aow any flags, but that's not going to happen. The college flags are some of the worst propoganda placed in public schools today, but no one seems to care.