- Dawson Casting: Played straight with Jonah Hill, avoided with Emma Stone, Michael Cera and Christopher Mintz-Plasse. Commentary for the film tells the story that Judd Apatow had to be convinced that Jonah could pull off the role age-wise. Originally the role was for Seth Rogen (who wrote it) but was deemed too old at 25; Jonah Hill ended up in the role despite being just a year younger than Rogen. Rogen admits freely that he's looked thirty since he was about fifteen. Because he was a minor, Christopher Mintz-Plasse's mother was required by law to be on the set when Fogell loses his virginity.
- Hey, It's That Guy!:
- The cops are played by Bill Hader (who was an SNL cast member at the time of the movie's release and popularity) and Knocked Up's Seth Rogen for starters. What's funny is that Bill Hader is also the voice of Mickey the bank robber on the FOX animated sitcom Bob's Burgers, so Hader has played both a cop and a criminal (even though his cop character on Superbad isn't exactly law-abiding either).
- Uncle Eddie does not want Francis at his party.
- Clark Duke (Hot Tub Time Machine and Greek) can be seen as one of the guests at Jules' party.
- Emma Stone as "Jules". This was her first movie role.
- Ally Dawson was young Beca
- I Am Not Spock: Poor Mintz-Plasse...
- Throw It In: A surprising amount of the jokes were purely ad-libbed by the cast, usually until something was funny enough to cause the actors to break down laughing, and thusly added to the script.