I remember that there was an autistic fellow in one of my Japanese classes in my shitty community college at one point. ("JPN 102 - Conversational Japanese", required JPN 101)
Quite a big, 6-foot-something, overweight guy, white as snow, had curly light brown hair. Always wore the same long sleeve gray shirt with matching sweat pants. Smelled like warm ass. I swear to god this wasn't Chris-Chan.
He often giggled and sometimes "REEEEEEEEEEEEE'd" at literally random, inappropriate moments, regardless if the professor was in the middle of lecturing or we were all quietly doing a test. Always startled somebody, especially the poor teacher (the nicest Japanese 50-something lady ever). We often had to ignore his strange outbursts because "oh, he might be retarded, let's try not to offend".
There was a really cute Chinese girl, only a young teenager (13 or 14) that attended my Japanese classes after middle school, because she was advanced or something. Every start of class, the autistic lummox tried to hug her like a deranged bear (as well as screeched like an opossum) whenever she was near, so me and a group of friends got her sitting with us in the very opposite corner of the room from the big guy. She was fucking terrified of him.
Another interaction in class was with a very... androgynous student. This student had a long pony tail, dressed in Hot Topic goth shit, and the voice was like a higher-pitched Dana Hill. I seriously could not identify the gender of this person, and no one bothered to ask at risk of offending. Well, nobody but our autistic oaf. One class, in the middle of a lecture about Japanese language politeness suffixes, the big lug got up while the teacher had her back turned to the class, walked directly to the front of Androgynous-ladyman's desk, and loudly asked, "SO ARE YOU A BOY OR A GIRRRLLLLLL?". He/she gave a very frustrated "ugh, are you kidding me?!" and stormed out of the classroom. Big guy casually shrugged and sat back down like nothing happened. I still do not know the gender to this day, everybody else remained too afraid to ask. He popped out a Nintendo DS and the teacher stopped giving a shit about his autistic antics at that point.
There was also a time when we were doing presentations to the class by saying some Japanese shit to test what we learned. Some did oral speeches, some did little videos/animations we presented from the projector -- I did the latter. As soon as my video presentation was done, he waddled over to the computer, pushed me out of the way, fumbled through YouTube, and brought up a fucking YouTube Poop video that blared extremely loud nonsense through the projector's rattling speakers. The teacher was bewildered, and another student had to get up and close the video (with such massive disdain in her face) for the sake of everybody's ears. The teacher tried asking people if they knew the number for this guy's parents (mind you, he was 20-something). Nobody knew, and the class ended shortly after.
He didn't speak a single goddamn lick of Japanese the entire time there. He eventually stopped showing up after about 3/4 of the semester in, so I'm pretty sure he was dropped out of class because he was always an amusing, yet disruptive spectacle.
Sorry, your post immediately reminded me of my one class I took some several years ago.
While professors always proclaim on their syllabus that they'll make accommodations to students with special needs, I think they're hardly ever prepared for students like this. You must need dedicated departments that deal exclusively with special needs students and know how to effectively teach college-level material around their quirks.
Honestly, I don't think higher education funds this part really well because you never really hear of autistic students making it big, let alone follow up successfully on whatever degree they study. (but this is as far as my lazy NEET ass knows)
That's my two C-Quarters.