I know who Screech from the cult TV classic Saved By the Bell is cheering for: the 49ers. That's because on the TV show, Screech's cousin was Jim Harbaugh. The onetime Bears and Colts quarterback who is now the coach of the 49ers.
Harbaugh's appearance was in an episode called "Litte Hero," which aired on Sept. 21, 1996. And it wasn't the original Saved By the Bell, but rather the follow-up Saved By the Bell: The New Class. The original series had Mark-Paul Gosselaar, Mario Lopez, Elizabeth Berkley and Tiffani Thiessen, among others. In the sequel series (The New Class), Screech - played by Dustin Diamond - was the only one of the original main characters who remained.
Here is the scene in which Harbaugh appears as Screech's cousin:
That wasn't Harbaugh's first appearance in a network television series, however. In 1994, Harbaugh - along with Terry Bradshaw, Ken Norton Jr. and Carl Banks - guested in an episode of The Adventures of Brisco County Jr.:
After watching these, it's clear why Harbaugh stuck with his day job.