Good Morning, Mr. Grumpfish! is the 11th episode from Season 3.
While Mr. Grumpfish is their substitute teacher, the children teach him about their favorite things by singing about them.
The episode starts when Molly greets herself to the audience. Then she is interrupting because Gil has headphones over his ears and he is singing Restaurant. After he sings The Restaurant, Super, Super, Supermarket, and It's a Beautiful Day.
The episode starts off going into the guppies' school. After all were seated, they were surprised to see Mr. Grumpfish and wondering why he was there. Gil asks where is Mr. Grouper and in reply, Mr. Grumpfish said that he was at the dentist and that he'll be back later. The guppies then we're asking what they are going to do that day, anything special. Mr. Grumpfish said no, because it's raining. The guppies look outside the window and Goby said that it's not raining. Then Mr. Grumpfish said that it might and he doesn't like the rain, "Too wet." Oona assured him that it wasn't going to rain, that it's a pretty spring day. Mr. Grumpfish asked what's so great about and all the guppies replied "Let's sing about it!" and they sang It's a Beautiful Day.
Then, the guppies play Deema's supermarket. Deema, at the cashier, sees Mr. Grumpfish coming and asks if she can help him find something. Mr. Grumpfish didn't really understood. Deema said that everything that he needs can be found and have Supermarket. He asks what's so super about the supermarket and Oona said "Let's sing about it!" and they sang Super, Super, Supermarket.
Next, the guppies were coloring and saying what they were drawing and their favorite color. Molly asks Mr. Grumpfish what's his favorite color. He said that he doesn't have one, not even greenish-brown as Deema said (she drew a picture of him). Mr. Grumpfish said that he doesn't like colors....too colorful and asks what's so great about colors. And the guppies reply: "Let's sing about it!" and they sang A Color Just Right.
Afterwards the guppies are playing now restaurant. Molly takes Nonny and Mr. Grumpfish order. Nonny said they'll take the lunch special. Gil comes with a plate covered. Mr. Grumpfish asks what is it and Gil says that the lunch special is three chicken surprise. He uncovers the plate and there were only two chickens. Mr. Grumpfish asks why are they only two chickens and Deema appears behind Mr. Grumpfish with a chicken puppet and says "Surprise!" and makes chicken noises. Everybody laughs, except Mr. Grumpfish says he doesn't like restaurants. "Too surprising." Oona, who was sitting with Goby was shocked that he doesn't like restaurants either. Again, he asks what's so great about restaurants and the guppies say, "Let's sing about it!" and sang The Restaurant.
The guppies then go outside to play. Mr. Grumpfish comes by to make sure everyone is ok. Then they ask him if he wants to play with them but he said no. Then he goes over to Nonny who was by himself at the sandbox. Mr. Grumpfish asks him what he was doing and Nonny said that he was looking for dinosaur fossils. Mr. Grumpfish didn't really understood so Nonny explained that were fossils, leaving him instrested. He swims away alittle and asks Nonny what else does he know about dinosaurs and he replies, "Let's sing about it." They sang Long Time Ago.
Afterwards, they were playing hospital. Gil had an ambulance and was making sirens noises around the classroom, with Bubble Puppy chasing after him. He passes by Mr. Grumpfish and Molly. Molly as being a doctor and checking her list, her next patient was bubble puppy. She checks his tongue, ears and tail. Then Nonny comes with a drawing of Bubble Puppy's X-Ray of his tail and reminds the audience what an X-ray is. "Everything looks good!" says Molly. Then Mr. Grumpfish arrives and asks what is the picture of. Gil replies that it's an X-ray of Bubble Puppy's bones. Molly continues that bones are very important. Mr. Grumpfish asks if they are going to sing about it and Molly responds with a nod. Song: Got a Bunch of Bones.
Then, while Mr. Grumpfish was cleaning up, he heard the guppies singing a short version of Sun, Beautiful Sun. He looked up and they said that their planets and they're orbiting. Then Deema asked him if he wanted to be the sun. Mr. Grumpfish wasn't sure but the guppies convinced him. They hand him a yellow ball and sunglasses. Deema continued on saying that now he looks like a star. Nonny said that the sun is a star. Mr. Grumpfish said far out and all the guppies said, "Let's sing about it!" Song: Sun, Beautiful Sun.
Finally Mr. Grouper came back from his dentist appointment and the guppies go and hug him. He asks them how was their day and they told them everything. Then Mr. Grouper asks Mr. Grumpfish if he had learned anything new and he said that he did learn a few things. Deema goes up to him and asks him like what. His response, "Let's sing about it." Song: Sing About Everything. After the song, Mr. Grouper tells the guppies that he thinks that Mr. Grumpfish likes them, to which Mr. Grumpfish says that he loves these guys. Molly and Gil go up to him and gave him a hug and the other guppies cheered.