Rainbow Fish s01e03
Titre original : Rainbow Gets an 'A; Grandpa's Fishy Tale
Rainbow Fish gets a bad report card, but after he spills a kelp gusher on it, his parents mistake the "C" grade for an "A". Rainbow must prevent them from meeting Principal Gefilte and learning the truth.
Rainbow is not enthusiastic about spending time with his grandpa while his parents are away at the store, thinking he will be bored, but when his grandpa tells him an amazing story that hides an incredible secret, Rainbow discovers that old people can be exciting after all.