1. The film’s gut-wrenching heart-to-heart, where all five kids spill deep, dark secrets, was ad-libbed.
2. The movie was initially conceived of as a franchise-starter, with subsequent entries “checking in” on the characters.
3. A dream sequence, in which Allison (Ally Sheedy) imagines Andrew as a gluttonous Viking, Bender as a prisoner, Claire as a bride, Brian as an astronaut, and herself as a vampire, was cut from the final version.
4. Another scene, that featured a pair of high school teachers–Dr. Lange, a social studies teacher, and gym teacher Robin–was also chopped from the final version.
5. As a student, Carl the janitor was Shermer High’s ‘Man of the Year.’
6. Rick Moranis was originally cast as the janitor, but was replaced due to “creative differences” (he wanted to play the part as an over-the-top Russian stereotype). The role was ultimately played by John Kapelos.
7. The film was rehearsed in a manner more similar to that of stage plays.
8. Emilio Estevez was originally slated to play Bender, but Hughes couldn’t find anyone else who was right for the Andrew role, so Estevez ultimately switched and the Bender gig went to Judd Nelson.
9. Similarly, Molly Ringwald was first asked to play Allison, but she wanted the Claire (named “Cathy” in the first draft of the script) role. Hughes eventually let her have it.
10. Other actresses that could have played Claire? Robin Wright, Jodie Foster, and Laura Dern, who all auditioned for the part.
11. Anthony Michael Hall’s mother and sister appear as his character’s mother and sister in the beginning of the film.
12. Another parent to look out for? Hughes, who had a cameo role as Brian’s father at the end of the film.
13. Brat Pack members Sheedy, Estevez, and Nelson starred (as college graduates) in St. Elmo’s Fire the same year that The Breakfast Club hit theaters.
14. Allison’s dandruff, which she sprinkles to “make it snow,” was made of Parmesan cheese.
15. John Cusack was also considered for the role of Bender, as was Nicolas Cage.
16. Like a number of other Hughes films, including Weird Science, Ferris Bueller’s Day Off, Sixteen Candles, Pretty in Pink, and National Lampoon’s Vacation, the film is set in the fictional Chicago suburb of Shermer, Illinois.
17. Judd Nelson was the oldest cast member at the time of filming; he was 26.
18. Sheedy doesn’t speak for the first 33 minutes of the film.
19. As an end-of-filming present, Hughes gave each actor a piece of the “library’s” banister.
20. Hughes had planned for The Breakfast Club to be his directorial debut, but the studio went for Sixteen Candles first.
21. Brian’s social security number, as filched by Allison, indicates that he was born in Connecticut.
22. The marijuana the kids smoke in the film was actually oregano.
reposted from Mental_Floss