During the car chase on campus, the action in one particular scene is sped up and a tune similar to the iconic music from Benny Hill can be heard. In the background, the building title reads "Benjamin Hill Institute for Film Studies"
Seth Rogen appears as a replacement for Jonah Hill in a mock sequel. One of Hill's earliest roles was in Superbad (2007) as Seth, a character Rogen had envisioned playing himself when he began writing the script as a teenager.
When Schmidt and Jenko go to the Psychology professor's office, the nameplate on the door says Michael P. Murphy. Later, when Deputy Chief Hardy (Nick Offerman) gives the TV press conference saying that they caught the dealer, he says the name is Carl Murphy.
Just after the library scene where Jenko drops down one landing at a time and then jumps over the railing, his shoes are flat-soled, instead of the cleats he should be wearing with his football uniform.
The film is a sequel to 21 Jump Street, which is a sequel/reboot of the television series 21 Jump Street, with the screenplay written by Michael Bacall.
Q
Are there any cameos from the series?
A
Greg shares the same last name as Captain Richard Jenko (Frederic Forrest). Richard Grieco makes a cameo appearance as Dennis Booker.
Q
What are the "sequels" shown in the end credits?
A
Here are all of the sequels: http://news.moviefone.com/2014/09/26/here-are-all-the-fake-22-jump-street-sequels-photos/