At Ohio State some of the things that are done:
Sororities
KD Slapshot (Shamrock Hockey Tournament)
DG Anchor Slam/Splash
Kappa Kappa Dog Night
AOPi NachoFest
Tri Delt Kicks for Kids
Alpha Phi Mud Tug
DZ Spaghetti Dinner
ChiO Moon Ball
Fraternities:
TKE Softball
Beta Bowling
Phi Psi PhiPsi500 (By far my fave!!)
SAE E Ball
Pike Powderpuff Football
Phi Tau Pumpkin Sale (Way more fun than it sounds!!)
Lamda Chi Watermelon Bust
Sammy Poker Tournament
Sigma Chi Derby Days
These are only the big ones. I couldn't think of some of the lesser known events that some of the houses hold every year.