- Actor Allusion: Perhaps it was unintentional, but:
Walter: I'm not mean, Danny, I'm in fourth grade, I have a girlfriend.
- The Cameo: Tim Robbins has a cameo as Walter and Danny's father.
- Fan Nickname: "Zenthura," for those who watched the episode of The Apprentice where one of the candidates repeatedly referred to the film by that name in an all-important presentation to Jon Favreau himself.
- Playing Against Type: Watch Kristen Stewart as the decidedly emotional Lisa and then say her acting only consists of Dull Surprise.
- Screwed by the Network: Putting this up against Harry Potter and the Goblet of Fire was a surefire way to ensure that the film wouldn't be a box-office success.
- What Could Have Been: Dax Shepard (who plays the Astronaut) said once that when he signed on to the film, the script was meant to be more of a sci-fi action epic, with the two young brothers fighting and trying to get along being more of a subplot. But, then executives decided, the boys learning to get along should be the core of the film, and a lot of the space fight sequences got taken out.