Maya Forbes' sister, China Forbes, performs the song "The Northern Line" over the end credits, a song for which she also composed and wrote the lyrics.
The film takes place in 1978.
Mark Ruffalo's character tells his family, when the van is about to leave, that he wishes he wasn't dressed like a big green bug (green Polo Shirt and matching shorts). For years, Ruffalo played the Incredible Hulk, who is notoriously big and green.
Mark Ruffalo and Zoe Saldana appeared in the Marvel Cinematic Universe as Bruce Banner/The Incredible Hulk and Gamora respectively. They would both go on to appear together as those characters in Avengers: Infinity War (2018) and Avengers: Endgame (2019).