I can't speak for what is popular on your campus, but in my day we usually had theme parties. For really quick ideas on decorations/costumes/etc, I can offer up two great websites:
http://www.orientaltrading.com
and for the more exotic costumes,
http://www.hollywood-costumes.com
The Oriental Trading Company one will probably be more helpful for your first party and getting ideas and costs of options.
We usually had a keg in one corner, mixed drinks in another, non-alcoholic in the third, and food in the fourth, so that most people flowed around the room. Dancing/band on back end, lights/fog machine if fitting theme, and usually
college students + alcohol + music = great party.
Some themes I remember most are the 70's party with "bring your own pillow" for the sit-in/sleep-over affect, the Egyptian party with flowing mixed drink pyamid and take-your-photo-as-a-sphynx/cleopatra sort of thing happening, and a Mardi-Gras Crawfish Boil with Tshirts proclaiming "I sucked the Head!" given to anyone who did so. A little crass, but it was sooooooo delicious and fun.
Hope this helps to get you started!