What are the most popular student activities/groups?
Social life revolves around the in-season teams' game schedules. When teams are off campus for games, it's very noticeable. Weekends are Thursday through Saturday, with a sprinkling of random evenings when you and your friends don't have too much work (although rare is the evening when your no-work evenings overlap with your friends'). Fridays are surprisingly quiet, mostly because athletes are resting up for their Saturday games. For freshman, particulary during the first months when not all of them have 21-year old friends yet, weekends mean college house parties and long keg lines, which get old fast. Most upper classmen steer clear of these parties, unless they're other college house members or it's a particular themed party. The dating scene is a hookup scene.
Campus Activities Board and other organizations do a very good job of bringing acts to campus - recent performers have been Talib Kweli, Ben Kweller, and Girl Talk. Multicultural groups are surprisingly quiet and border on nonexistent, while sexual health and awareness is a big thing on campus. A Cappella and comedy groups are strong as well.