The only school I know of with one is UC Davis; my good friend goes there and is on a club/intramural/whatever quidditch team. Sorry UC Davis is in California, though, but when my friend told me about it she made Davis seem reflective of a growing trend for colleges to have them - I am sure there are many more schools that have it. To all you other answerers, some colleges actually do have quidditch teams, in the same category as intramural ultimate frisbee and the like; its actually legit. They have all the positions who play as regularly as is possible without flying, and then they have someone who dresses in all gold and runs around the field acting as the snitch, who the seekers then attempt to catch.
