Clint Howard screamed and yelled at the top of his lungs while driving in a car every day to the set in order to have a more gravelly voice for his role as Gregory.
This movie was sponsored in part by the Converse shoe company. Many characters wear Converse shoes, especially the classic Chuck Taylor All-Stars. There is also an extraordinary number of shots of shoes throughout the entire film.
Mashed potatoes were used as a substitute for ice cream in a lot of shots.
The first draft of the script was written in three days.