A story I just read reported research finding men's grades dropping when their school's football team has a winning season. The research was done at my doctoral dear mother - the University of Oregon. See the story here on the USA Today website.
I spent three very rainy years in Eugene, Oregon, working on my Ph.D., as well as attending home football games and post-game parties. I guess I was fortunate the football team lost a lot of games those three years as my grades weren't bad.