In fact, Landis actually knew Bernstein when he was a kid, and had actually gone to school with his son, Peter.
Hey, It's That Guy! : D-Day is played by veteran character actor Bruce McGill. Flounder is Stephen Furst, later a regular on St. Elsewhere and Babylon 5. Tom Hulce (Pinto) would go on to an Academy Award nomination for the title role in Amadeus, and later voiced and sang the title role in The Hunchback of Notre Dame. Tim Matheson played Otter, and is pretty recognizable now as Vice President Hoynes and "Dead" Larry Sizemore. Also, Mark Metcalf, who played Niedermeyer, did his yelling schtick in the beginning of Twisted Sister's famous "I Wanna Rock" video, and later, albeit under heavy makeup played Kool-Aid MouthThe Master. And the same actress who played Mrs. Wormer was also the Virgin Mary.
Throw It In: When Bluto is sneaking around the campus at night and slips, rolls around and casually stands back up, that was an actual slip-up by Belushi from the very wet grass on the location. The director thought it was the funniest take and used it.