When Dexter is asked to bring his mother to school, he disguises Dee Dee as her so that she can take her place, but Dee Dee does not behave like their mother.

A nature documentary team observes “Blackfoot” (Dexter) and “Slim” (Dee Dee) in their “natural habitat”.

When an intelligence test grades Dexter as “average”, he shuts down his lab and tries to live life like a normal kid.

When Dexter’s father tries to teach his son sports, he realizes that Dexter is not athletic.

After fellow Justice Friend White Tiger helps Valhallen stop a super-villain, the latter invites him to spend the night in his apartment, forgetting that Major Glory is allergic to cats.

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

Dexter is upset that Dee Dee is more photogenic than him, so he transforms his face into a handsome one for his next Picture Day.

To fix their apartment’s plumbing, Krunk and Valhallen go to the basement, where they meet Ratman (Maurice LaMarche), a diminutive vigilante raised by rats (a parody of Batman).

When his television show is interrupted by the Emergency Broadcast System, Dexter sets about fixing any emergencies in the neighborhood to make the signal go away.

Banned from watching a late-night movie due to his young age, Dexter uses his technology to artificially grow into adulthood, but Dee Dee tampers with his machine, causing Dexter to turn into an old man.

Dee Dee wins a golden diskette, earning her a free trip to the laboratory of Professor Hawk (Tom Kenny), one of Dexter’s favorite scientists.

After Dexter’s pencil rolls to the back of the school bus, Dexter goes to retrieve it, but legend says that no one has ever returned from the back of the bus.

Rerun of the second What a Cartoon! pilot.

When Dexter cannot reach anything in his lab, he makes himself more flexible by combining himself with bubble gum.

Dexter and his friends are targeted by a bully at school for their multicultural accents.

When Dee Dee takes photographs of his lab, Dexter goes on an adventure to retrieve the photos before his parents see them.

After Dexter orders and eats a giant burrito, he suffers severe stomach pains. Believing a test the computer gave him, he assumes that he has only 30 minutes to live.

Dexter invents a robot parrot that happily repeats self-congratulatory comments he makes, but when it starts repeating things about his lab and escapes, he sets out to destroy it before it tattles to his parents.

When Dexter’s friends become tired of his complicated traps and cheating while playing a role-playing game, they put Dee Dee in his place. She changes the style of play, which annoys Dexter but impresses his friends.

Dexter’s newest invention looks like a hat, so Dee Dee takes it and wears it around town.

Dexter and Mandark bring the Abraham Lincoln and George Washington faces respectively on Mount Rushmore to life and make them fight each other to determine who is the best.

Dexter makes his own Major Glory action figures so that he can join the neighborhood’s Major Glory gang, but gets into serious trouble when the rest of the gang finds out that none of his action figures are original.

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.

Despite warnings from the computer, Dexter consumes too much power while performing numerous experiments, causing his lab to shut down.

Dad decides to give the car a retouch, but keeps breaking things and saying he will fix it later. After having enough, he pushes the car over a cliff, and below it are other crushed cars, meaning this was not the first time.

When Dee Dee’s Judo skills prove too much for Dexter, Dexter learns how to fight back at the same dojo she went to.

After Dee Dee steals his critical invention, Dexter ventures into her room to find it.

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

Dexter and Dee Dee listen in on their parents’ conversation; they are playing Scrabble, but the way they talk makes it sound like Dad was cheating on Mom

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

Dexter creates a device to make a lifelike superhero comic, with his sister villain “Deestructa”.

Dexter’s father is left to watch the kids while his wife visits her sister.