1. Sean Astin (Mikey Walsh) took home Willy L’Orbo’s map, but years later his mother (Patty Duke) thought it was waste paper and threw it away.
2. In the movie, Data tells his parents about a scary giant octopus. It was not his fantasy but a scene that was then cut from the final cut.
3. The pirate ship was actually built with pieces from the “Pirates of the Caribbean” attraction at Disneyland. The young protagonists knew nothing about it, to keep their amazement intact. At the first take, however, Josh Brolin (Brandon) cursed seeing her and for this they had to turn the scene.
4. John Matuszak played Sloth. In his career he had been a football player for the Okland Raiders and in the film he has the team shirt. He died of a heart attack four years after the release of the film at the age of 38.
5. Robert Davi (Jake Fratelli) had the idea of making his character sing opera pieces, because he had studied singing in his youth.
6. Director Richard Donner is one of the cops at the end on the beach.
7. In Italy many believed that Mamma Fratelli was a man because she was voiced by Vittorio Stagni. Actress Anne Ramsey died three years after the film was released.
8. It took 5 hours a day to transform John Matuszak into Sloth.
9. Jeff Cohen (Chunk) became an entertainment rights attorney.
10. The deleted rain scene was then inserted into the video for the film’s song sung by Cindy Lauper.
11. The term “Goonies” derives from the neighborhood where the protagonists “Goon Docks” live. In American slang “Goony” means “Loser”.
12. For the part of Mouth, which went to Corey Feldman, Corey Haim is also proposed. Years later the two became famous as the two Coreys and often worked together.
13. The ship was put up for auction but then scrapped for lack of buyers.
14. In a fight scene between brothers Mikey and Brandon, Sean Astin calls his “brother” by his real name… Josh (Brolin).
15. The policeman, who doesn’t believe Chunk on the phone, tells him: “like that dance of monsters that multiply if you throw water on them”. The quote refers to “The Gremlins” always scripted by Chris Columbus.
16. Willy L’Orbo’s skull was a real human skull.
17. The film was shot almost entirely in sequence to help the young protagonists to identify themselves better with the story.
18. Jeff Cohen (Chunk) did not say he had chickenpox early in the shoot, for fear of losing the role.
19. To look realistically ancient, the map was soiled by the set designer with coffee… and his own blood.
20. Jeff Cohen’s (Chunk) real family members are all present at the end of the film, even his sister Eydie … same name as Chunk’s sister “thrown down the stairs”.