Fred Berry and Ernest Thomas walked off the show during the second season, demanding more money and better dressing rooms. Their demands were met. After the third season, Berry and Thomas convinced Haywood Nelson to join them in another walkout demanding more money. Even though the show ranked 29th in the 1978-1979 season, ABC canceled it rather than deal with their demands.
During production, Danielle Spencer was involved in a car accident which left her in a coma for a few days. When Spencer came back to work, she had to do most of her scenes sitting down to avoid physical exertion, and changed her hair style and bangs to cover up injuries on her forehead.
Mabel King wanted the Thomas family to have a mother and a father (on the air Roger and Dee's parents were divorced, and their father remarried in 1977 and was not seen again). The producers' refusal contributed to her decision to quit her role in 1978. King was also unhappy with her reduced role in the series.
According to Haywood Nelson, he was in a relationship with Debbi Morgan, who played the recurring role of Diane. But Nelson said that he was not mature enough at the time to commit to their relationship.
Eric Monte sued the producers, claiming he did not receive proper credit as the creator of the series. A title card at the very end of the end credits read "Suggested by the American International picture Cooley High written by Eric Monte". He also claimed that he was promised a credit as a producer. He received an out-of-court settlement.