The Breakfast Club/Trivia
- Dawson Casting: Judd Nelson was 24 at the time, and Ally Sheedy and Emilio Estevez were both 22. Averted with Molly Ringwald and Anthony Michael Hall, both 16 at the time.
- Enforced Method Acting: Judd Nelson remained in-character between shooting, and frequently taunted Molly Ringwald to the point of tears. John Hughes was on the verge of firing him, when Paul Gleason, ironically playing Principal Vernon, intervened on his behalf.
- Executive Meddling: The studio wanted a scene involving a sexual situation, since this was a teen movie in The Eighties and movies like Porky's were still on executives' minds. So Hughes wrote and filmed a scene where Vernon spies on a female teacher (played by Karen Leigh Hopkins) swimming nude in the school's swimming pool. Obviously, Hughes ended up cutting out this scene entirely because it hurt the tone of the film.
- Real Life Relatives: Anthony Michael Hall’s sister Mary Christian and mother Mercedes Hall plays his character’s Brian Johnson’s sister and mother.
- Throw It In: 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...
- What Could Have Been: 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 instead, and let Judd Nelson play Bender instead
- In addition, Rick Moranis was originally cast as Carl, but he left due to creative differences and was replaced by John Kapelos.
- 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.