When Billy Madison apologies to Danny McGrath for being mean to him in high school, Danny crossed Billy's name off the People To Kill list. The eight other people left on the list are all crew members of the movie.
The 20 Categories listed during the final stage of the Academic Decathlon are: English Literature, U.S. Presidents, My Wife The Tramp, Astronomy, Baking, Burning Dog Poo & The Human Response, Reflections Of Society In Literature, Information Systems, Chemistry, The Roman Empire, My Spouse Is Sleeping Around, The French Revolution, Automotive Repair, 20th Century Poetry, Calculus, Needlepoint, Architecture, Business Ethics, Shakespeare, and I Married Common Street Trash.
Cast members Larry Hankin and Mark Beltzman previously appeared together in film Home Alone (1990). Hankin and Beltzman also guest starred, in separate episodes, on the popular NBC sitcom "Seinfeld" (1989-1998).
Billy refers to the janitor as "Sideburns," based on his exaggerated sideburns. In The Wedding Singer (1998) Adam Sandler's character calls out a wedding attendee as "Sideburns" Lady based on her exaggerated sideburns.
While discussing video games with Scotty at lunch, Billy tells him that Donkey Kong (1981) is the greatest game. Years later Adam Sandler played a video game expert and will defeat several video game villains in Pixels (2015).