It has a gray exterior with green doors. It has the words "Puff's Boating School" transcribed on it in dark pink letters, with a lighter pink cloud around it.
Role in episode
Mrs. Puff's bus serves as the transportation of Mr. Krabs' band (consisting of SpongeBob and Squidward as the musicians and Patrick as the roadie). Mrs. Puff fixes her bus up until Mr. Krabs steals it from her when she isn't looking. With it, Mr. Krabs drives to many different venues until he is able to buy back the Krusty Krab at the end of the episode.