Stuffing phonebooths (remember those)? Sitting on flagpoles? Demonstrating? Streaking?
Perhaps one of your ancestors was a student class president. Scored the winning touchdown in the championship football game. Member of the debate team. Voted most likely to succeed...or go to jail! Whatever academic superlatives and shennanigans lie in their past, there are some very useful tools for unearthing some of their high school, college and university history.
First and foremost, are scattered but often fairly deep collections of college newspapers. If you're lucky, and grandpa's alma mater has its newspaper archives online, then you've struck gold. Granddad may well have been written up in the student paper, but even if he wasn't, you can still come away with a good overview of what campus life was like back in the day.
Most college newspaper archives extend back at least to the early 20th century. The University of Richmond, in Virginia, has free online archives dating back to 1914, while Barnard College in New York City goes back to 1901. Not to be outdone, the Harvard Crimson dates all the way back to 1873, while its neighbor at U Mass only manages to date back to 1966.
Here's a good list of free college newspaper archives, so you can explore what's available.
There's a ton of archived high school and college yearbooks scattered about, like this 100-year collection of yearbooks from Penn State, or the Columbus, Indiana High School collection of yearbooks.
These can be a lot of fun to browse, but you need to do some scouting around to find them. A good trick is to search one of the commercial yearbooks sites like e-yearbook or even ebay to see what exists in digitized form. If you find one, then search the web more generally to see if it's posted for free. If it's not, then you can purchase the yearbooks from the sites where you found them, if you're so inclined.
Don't forget to also check for your family history at Ancestry.com and NewspaperArchive. These are subscription databases, but they are among the most powerful research tools available for looking into family roots.