Gonna Party Tonight is a song that Thidwick the Moose, Mr. Knox, Fox in Socks, Fiona Phish, Morton the Elephant Bird and the Birthday Bird sing all about having a fun time at a party. As they dance around the Cat in the Hat and the Little Cats come in with a big birthday cake and start in with everyone else. Even the Gribbles join in after the Cat pokes them with his umbrella.

The song was featured on The Wubbulous World of Dr. Seuss, in the episode "The Birthday Moose".