After she expresses her desire to become a Pony Puff Princess, Dexter transforms Dee Dee into a horse with pink fur, and a yellow tail and mane.

Dexter and Koos must save Peepers to keep the land of Kooz from disappearing. However, they must contend with a villain who is determined to make the land of Kooz disappear forever.

Dexter finds out that all of Mandark’s plans are taken from a comic book.

Dexter’s parents get him a bike for exercise, but he’s unable to catch Dee Dee on her inline skates.

Dexter and Mandark’s fathers become embroiled in a conflict after trying to defuse one between their sons.

Mandark enters a surfing contest and tries to cheat his way to victory to win Dee Dee’s heart from another surfer.

When Dee Dee eats a contaminated apple, she turns into a monster every time when she tells Dexter what to do.

Dexter’s father tries to get himself and Dexter to his fishing spot before sunrise so that they can start fishing before others arrive.

Dexter invents a belt whose wearer can do anything backwards, but mayhem occurs when Dee Dee gets hold of the belt’s directional switch.

Quackor returns to battle Monkey in Dexter’s Lab until Quackor lays an egg; then the two fall in love.

Dexter is given detention after accidentally shouting out the answer to a test question.

When Dexter is tired of Dee Dee’s bad singing, he tries to transform her voice, but he ends up giving her a baritone voice (Kevin Michael Richardson).

Dexter accidentally gives himself telepathy that he cannot shut off when trying to overhear his father’s thoughts to figure out what he got for his birthday, causing everyone to accidentally read his own mind.

Unable to ride in a roller coaster due to his height, Dexter creates a device to make himself taller.

Dexter finds a lost Labrador Retriever, but when he teaches the dog to speak human language, he turns out to be very annoying, prompting Dexter to find the dog’s owner.

Dee Dee gets a song stuck in her head, which is actually a virus. Dexter and Mom soon catch it, and Dexter has to reverse the effects of this. He succeeds at the end, not knowing that Dad also caught it.

Dexter creates a robot to assist him, but the robot starts controlling his lab and tries to destroy Dexter.

When Dexter’s glasses break, he creates a new fad (wearing broken glasses) and becomes extremely popular at his school.

When Dee Dee causes Dexter to mistakenly take a book from the library without checking it out, they sneak into the library at night to put it back.

Dexter and Dee Dee experiment with coffee after seeing how it energizes their parents in the morning.

In a fit of rage, Dexter dumps Dee Dee’s favorite teddy bear into the garbage. An upset Dee Dee begins to behave oddly, prompting Dexter to go to the garbage dump and get it back.

Dee Dee’s stuffed animals come to life and roam the house when Dee Dee uses a formula that brings inanimate objects to life, which delights Dee Dee, much to his dismay.

Rerun of the second What a Cartoon! pilot.

Dexter is disappointed when he ends up at an Amish farm instead of a high-tech farm for summer camp. His attempts to modernize the Amish family do not go well.