Amarose, I can relate! The classroom is the hardest part for me, because of gum chewing, foot shaking, pen tapping, mostly the repetitive stuff. I sit in the front of the class, and sometimes wear one earplug. Needless to say I don't always socialize much in class.

Do you have a 504 plan? I do (although mine only has ADD, not SPD on it, but I only use it for SPD reasons since my ADD is under control). It allows me to take my tests in my college's testing center. At my old college ANYONE could use the testing center, but I assume that most are through a Disability Support Services Department and therefore require documentation. I was also able to get a single room once when I lived on campus by using my allergy to dust mites and my ADD as reasons for needing one. In reality, I was only using it for my SPD, but they didn't have to know that. It also cost a tad more (maybe $200?), but it helped alot.

What types of earplugs have you tried? The cheap, foam kinds I find work really well at dampening sound alot (while still allowing you to hear the teacher's voice) AND you can cut them to make them thinner if need be. Other companies also make ones of different sizes. Sometimes if I need one during a test, I'll put one in one ear and let my hair down to cover it up. I can block my other ear with my left hand if need be. It feels VERY awkward since I always imagine someone would walk up to me and ask me something, and then I would have to take it out and that would look weird, but nothing like that has happened.

Best Wishes!