All of the suggestions so far are pretty spot-on. We've been having an unseasonably warm winter up until now but, knowing Michigan, that won't last long. The thermal or fleece-lined pants/leggings will be your best friend. You don't need to go crazy regarding the coat, since you will only be here for the Winter term and coats are all over the place when it comes to price (and since you can layer up underneath anything you do get). I'd recommend looking for something with a hood that comes past your face so it will block the wind - quite often the sub-zero winds are the worst part of the winter weather (at least imho).
It doesn't sound as if you'll be needing to do a lot of walking to get from your dorm to your classes so any decent, waterproof boot should be good. I lived a bit off campus and took the bus into downtown so there was quite a bit of walking. These hand & toe warmers were an absolute necessity for me. I'd keep them in my boots, pockets, and gloves. I'm not sure how I would've survived waiting outside for the bus without them.
That all being said, have fun in Michigan and go blue!
How cold we talkin? I found that a base layer of Hotchillys helped me stay out in colder weather, and ride for much longer. I was previously only comfortable in mid-50s weather, now I'm fine in mid-40s. Below mid-40s I start needing heated gloves, and in the 30s I start needing a heated jacket liner and disposable toe warmers. Never ridden in below freezing weather, so can't help you there.
I should mention... what I do is mainly to maintain comfort, not survival/avoiding frostbite. I know I could technically tough it out and be out in colder weather with what I have, but I would be grumpy (and I have). One time it was so cold that my hands went completely numb yet felt like they were burning, and I had to pull over every 20 mins and use my Ducati's exhaust as a handwarmer just to physically continue. God that sucked.
Also, it sounds obvious, but the type of gear you need is not just dependent on the temperature outside, but also the wind, how fast you're riding, for how many hours you're out riding, and whether the sun is out or it's overcast/you're in shade. For me, going 45mph, for 45 min, in 45 degree weather was my limit before I started wishing I had heated gloves for comfort.
As for gear, a non-vented leather jacket with a thermal removable liner is actually weirdly insulating and kept me way warmer than I thought it would, but there's actual winter gear on Revzilla you should take a look at.
Edit: Oh, and definitely get a Balaclava! Loove this TurtleFur one.
I seem to do just fine with these.
If the issue is cold while sitting, try using a Thermarest-Z-lite SOL (or similar) folded up on your chair, with the reflective side up. That will help insulate your booty while reflecting the heat your body generates back at you. Then you can unfold it and use it under your sleeping bag/pad too.
Also, for socks, I know you said you just got some. I found (after MUCH trial and error and many cold feet) that socks with at least 70% wool content are best. When my feet sweat (everyone's feet sweat) I found the higher content wool - even wet - would still insulate my feet and not make them feel cold. And when I'm sitting at a telescope observing the night sky, there are sticky-backed toe warmers (like this, or similar) you can add to your socks to help keep your toes warm.