Deleted Role: Several staff members were cut out of the script before filming. Dr. Lange, a social studies teacher who dresses oddly, and Robin, a gym teacher. Robin helps Vernon on a few workout machines until Vernon injures his back, and she eventually visits the students while they are in their circle in the library. Robin initially replaced many of Carl's scenes and Carl was originally set to be a minor character with only two scenes.
When Andy's father tells him, "No school's going to give a scholarship to a discipline case", he originally followed up with "Not a white one, anyway."
Carl predicts where the five kids will be in 30 years. Bender will have killed himself, Claire will have had "2 boob jobs and a face lift," Brian will have become very successful but die of a heart attack due to the stress of the high paying job. Allison will be a great poet but no one will care, and Andrew will marry a gorgeous airline stewardess who will become fat after having kids.
In a dream sequence, Allison imagines Andrew as a gluttonous Viking, Bender as a prisoner, Claire as a bride, Brian as an astronaut, and herself as a vampire. In an unfilmed alternative to this dream sequence, all five kids imagine random things, including cars, naked women, Godzilla, beer, and fighter planes, and these things end up filling the room until Vernon interrupts.
After Bender demonstrates "Life at Big Bri's house" Brian stops Bender and corrects him with a much more pessimistic version of the skit. Claire then proceeds to act out her life before asking Bender to demonstrate his version. Bender's routine changes as well here. After Bender mimics his mom, he stops, commenting that "then they make me work to pay off the dentist for the teeth HE busts."
The scene where Andrew and Allison are walking to get the sodas is extended to a point where Allison pulls out a pack of cigarettes and smokes one.
After getting the sodas, Bender shakes his can violently and places it among the five to see who gets the rigged one. Allison ends up getting it, and when she opens the can, all the soda squirts directly into her mouth.
After Vernon asks who has to use the lavatory, the five go to the bathroom. Vernon gives the boys 2 minutes and the girls 3 minutes. Claire catches Allison in a stall eating a bag of chips, repulsing her. Bender mocks Brian for sitting down to pee instead of using a urinal.
When the group is sitting in the circle and Allison mentions that she can write (and do other things) with her toes, she was going to follow up with an actual demonstration.
Additional cut content includes an extended version of the pot smoking scene, in which Brian and Claire are seen singing "All My Lovin'" by The Beatles and a new scene in which Allison breaks into the teachers' lockers using a switchblade, where she finds a copy of the Prince album 1999, remarking "You know what this means? They're human." Several other differences between the definitive and uncut versions of the film have been noted, chiefly an extended make out scene, in which not only Bender and Claire are seen kissing, but also Andy and Allison; lastly, during Hughes' small cameo as Brian's dad in the final scene (a performance which he later criticized), he was originally given the short line “Buckle up.”
The original film's running time was close to two and a half hours long, thanks to a lot of improvised scenes by the cast. The studio said no audience would sit through a teen movie of that length and ordered trims. A few small scenes have surfaced in the trailers and the TV version to replace some of the censored footage, but most has never been released.
Missing Trailer Scene: The theatrical trailer shows brief footage that was ultimately never used. One shot shows Allison sitting by herself in a small room (presumably while the rest of the kids are getting high). Another brief clip shows Allison (post makeover) explaining to Andrew that she doesn't wanna be alone anymore, to which he responds that she doesn't have to be.
Real Life Relatives: Anthony Michael Hall’s sister Mary Christian and mother Mercedes Hall plays his character’s Brian Johnson’s sister and mother.
Stillborn Franchise: It was originally suggested that there would be several sequels, occurring every ten years, in which "The Breakfast Club" would get back together. This did not come to pass due to the volatile relationship between John Hughes and Judd Nelson. Hughes stated that he would never work with Nelson again. Also, it was unclear whether or not Hughes still held ill will against his oft-cast starlet, Molly Ringwald. They had a falling out in the late eighties after Ringwald declined the Lea Thompson role of Amanda Jones in Some Kind of Wonderful to pursue more adult roles, thus severing her relationship with Hughes.
John Hughes told Judd Nelson to make up something off the top of his head for when he was in the air vent. Naked blonde walks into a bar...
The scene in which all characters sit in a circle on the floor in the library and tell stories about why they were in detention was not scripted. Hughes told them all to ad-lib.
At the very closing part of the film where Bender raises his fist in defiance, that was actually ad-libbed. He was supposed to just walked into the sunset, so to speak, and John Hughes asked him to play around with a few actions. When he was done and they were finishing up, Judd Nelson threw his fist up without running it by anyone. Everyone loved it, and it has become an iconic symbol of the 1980's.
Nelson improvised the part when Bender hawks a loogie and catches it.
Ally Sheedy and Molly Ringwald actually auditioned for the others' role. Emilio Estevez was originally cast as Bender, but when no suitable actor was found for the part of Andy, he agreed to take that part instead, and they cast Judd Nelson as Bender.
Nicolas Cage was originally considered for John Bender but the production couldn't afford his salary at the time. John Cusack was considered as well, but John Hughes thought he didn't look threatening enough.
In addition, Rick Moranis was originally cast as Carl, but he left due to creative differences and was replaced by John Kapelos.
Originally, only Claire was supposed to dance, but Ringwald felt uncomfortable so Hughes had the entire cast dance.
Bender was not going to walk to school in the original script. He was going to be driven by his dad in a rusty tow truck, and have a brief fight with him before his dad drives off. Bender also tossed a bagged lunch, his father saying "You are a waste of lunch meat!"
Hughes considered a sequel detailing what would happen upon the club's return to school the following Monday, but realized that it would be too complex a story to tell in film, and would be a logistical nightmare with regards to the actors reprising their roles. He danced around the idea of a novel, but ultimately never got around to it. He also tossed around the idea of doing a sequel every ten years, showing where the club was at in their lives, but for the above reasons (and possibly because of the Downer Ending predicted for Bender in a deleted scene) he decided against it. It's a double shame when you consider that all five of the actors said they would have reprised their roles in a heartbeat.
Working Title: Detention, The Lunch Bunch and Library Revolution.
Write Who You Know: Vernon was based on a wrestling coach from John Hughes' high school who flunked him in gym. Hughes ran into him later, and the coach said the movie was good, but the teacher was a real jerk.