I think a classmate was a special education student because of an accent
Why would you think that about person's accent?
I'm solely basing my opinion of him on his accent
For one, there's nothing wrong with having a mental disability and using that as an insult is very low. You also shouldn't assume or stereotype someone just from their accent or people will think you are bigoted and not want to hang out with you.
But an accent shows a lack of sophistication. I mean why would you want to hang out with someone who can't speak a second language.
Many people don't speak a second language. It doesn't mean there is something wrong with them or that they're stupid. At least this person is trying.