Dexter tries to prove to Dee Dee that Santa Claus is not real and is in fact their father in disguise. He ends up paying for his mistake when he has captured the real Santa Claus.

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 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.

After watching an Action Hank movie on television, Dexter grows a synthetic beard to try to be cool, but the police mistake him for Action Hank himself.

Dee Dee’s father trains her to fight a gang of bicycle-riding rogues dressed as ninjas who target her paper route every morning.

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

A teleporter malfunction sends Dexter to an alien prison, prompting Dee Dee to go on a mission to save Dexter.

Again tired of being short, but mindful of his past failures, Dexter decides to make everyone shorter than himself.

Mandark gets in touch with nature.

Dee Dee goes and plays in her own “lab” after being kicked out of Dexter’s.

When Dee Dee hides the core of Dexter’s nuclear lamp, he must decipher her clues within one hour to find it.

Dexter’s new device allows him to study for the next day’s French test while sleeping. It malfunctions, causing a single phrase (omelette du fromage) to repeat throughout the night, causing Dexter to wake up the next morning speaking nothing else except omelette du fromage.

Dexter participates in the “Annual Soapbox Derby down Volcano Mountain”. This episode is a spoof of the popular Japanese manga/anime Speed Racer. In this episode, the movements and dialog deliveries of the characters are similar to anime. While Dexter parodies Speed Racer and his father parodies Pops Racer, Monkey parodies Chim-Chim and Dee Dee parodies […]

When Dexter neglects his metal-eating pet bug, it begins eating his lab as revenge.

Dee Dee builds a tree house and allows everyone inside except Dexter, in revenge for the times he kicked her out of his lab.

Dexter is trapped in his school by the janitor in revenge for making him work late everyday due to Dexter’s habit of leaving the school last everyday.

When Dexter’s new device, made to help him see through solid objects, fails to work as expected, he ends up seeing through people’s clothes, which puts him in an uncomfortable situation.

Dexter and Dee Dee realize that they make a good team, so they decide to do stuff together, but doing so makes things worse.

When Dexter catches Dee Dee killing ants, he shrinks them both to take her inside an ant colony so that she can learn how organized the ants are.

When their father makes Dexter and Dee Dee switch rooms, Dexter believes that Dee Dee is destroying his lab and destroys her room in retaliation.

The U.S. army invades Dexter’s lab under the mistaken impression that aliens are using it as a base of operations on Earth, and Dexter must convince them that this is actually his lab, and also has to keep this a secret from Dee Dee.

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

Dexter becomes the stern administrator of his local library.

Dee Dee and her friends, Lee Lee and Mee Mee, enter Dexter’s lab and wreak havoc. Dexter clones himself to stop them, but the girls too make clones of themselves.