Dexter, a boy-genius with a secret laboratory, constantly battles his sister Dee Dee, who always gains access despite his best efforts to keep her out, as well as his arch-rival and neighbor, Mandark.
Dee-Dee has a new boyfriend who also likes science and Einstein, and soon the boy finds himself caught in a vicious tug of war...
Dexter is hit by a wrench while working on a device, and suffers amnesia, Dee Dee decides to mess with his head
Dexter and Mandark drill underground to expand their labs, but end up overlapping each other's work. They secretly devise a plan to destroy each other.
Dee Dee accidentally breaks down Dexter's lab, and she tries to not and let him know its broken.
Dad wants cable really bad, so Dexter illegally pirates cable for him.
When Dexter becomes the head of a library, he inforces the rules really hard, driving everyone crazy.
Dee Dee learns a new game that can ""predict peoples futures"". She uses it on Dexter, and finds out that the game REALLY DOES predict peoples futures...
A Monster starts roaming Dexter's lab, although Dexter doesnt know its just Dee Dee, who ate an apple in a failed lab experiment.
Dexte'rs father begins to sleepwalk, and accidently stumbles into Dexter's Lab
Dexter accidentally shrinks his parents, and puts them into a model of there house. Although the house isnt completed, so Dexter must find a way to reverse it before they know the truth.
Dexter creates a new invention and wears it on his head. It suddenly becomes the latest fashion craze at Huber elementry.
Dexter and Dee Dee realise when they work together, they make a pretty good team.
Dee Dee has a song stuck in her head. Literally.
Dee Dee's stuffed animals come to life and roam the house. Dee Dee and Dexter must get them before Mom and Dad find out.
Dexter creates an ink in which lets him command them to do whatever he wants them to do. Although when Mandark gets a hold of it, Dexter is the one being the slave.
Decxter and Mandark are both outperformed by a new girl attending the school, jealous, they become allies to deal with her.
Mom thinks she should spend quality time and watch Dexter in his chess comatition. Although, she really embarasses Dexter while hes there...
Dad gets fired from his job, and has to do the same job Mom does. He realises it isnt as easy as it looks.
Dexter goes on a quest. His quest is to reach the bathroom before he explodes.
When Dexter realises the power of the potato, he redesigns his lab to work on it.
Dexter is tired of wearing glasses, so he uses laser surgery on his eyes to make him have 1/20 vision. Although, he learns than no human should be able to see THIS well...
Dee Dee goes over to Mandark's house to baby sit him, and Mandark likes that idea.
Mandark drops technology and starts being more in touch with nature.
Dexter decides its better if him and Mandark work together, although in the end Dexter does all the work while Mandark does nothing
Dexter is tired of being short, since his old plan of growing himself didnt work, he decides to make everyone shorter than him.
This takes place in the future, where Old Man Dexter tells about his ""glory days"". And Old lady Dee Dee keeps on adding her opinions as well...
When Dee Dee accidentally chops off her pigtail, Dexter gives her some hair growth potion. Although when she uses it, her hair floods the entire house.
When Dexter's Computer gets Laryngitus, Dexter must find a replacement voice for her.
Dexter refuses to see that blonde's have more fun, so he dyes Dee Dee's hair to prove it.
Dexter finds out that all of Mandark's plans are taken from a comic book. This way, he can get ready.
Dexter and his dad enter a Golf tournament, with Dad eager to get his hands on the Trophy, but there is one problem: he is hopeless at Golf, so Dexter decides to help with a remote controlled Golf ball
Dexter, Monkey, The Justice Freinds, Dee-Dee, her imaginary freind Coosie, Mandark, his parents, and Dexter's Parents participate in a cross-country race
Monkey narrates a documentry of the future of Laboratories and sciences.
Dexters parents accidentally sell Dexter's latest invention, and it is bought by Mandark.
Dee Dee starts layin' down the Judo on Dexter, then Dexter learns how to fight back.
Dexter falls in love with a new girl at his school, but decides to impress her with poetry rather than science.
When Dee Dee sees an Ostrage at the Zoo, she wants one of her own as a pet.