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.
When Dexter is bitten by a clown’s dentures, he begins turning into a mad clown every night, terrorizing the town with his mayhem, and only Dee Dee, who knows mime, can stop him.
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.
Dexter finds the exact opposite of his family, a hyperactive boy who is like Dee Dee and has scientist parents who are like Dexter. Sensing to fit in, he switches places with the boy.
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 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 travels to Mars to find intelligent life, unaware that Dee Dee has stowed away in his space capsule. After Dee Dee gets covered in red dirt, Dexter thinks she is a real-life Martian.
Dexter thinks that a crazy homeless person balancing electronic devices on his head and muttering gibberish is a genius trying to contact aliens, so he takes him home.
Dexter reluctantly takes piano lessons from Professor Williams (Paul Williams), but when the Professor stumbles onto Dexter’s lab, he discovers that Dexter has more musical talent than he thought.
When an electrician comes to Dexter’s house to repair a blown-out fuse, he accidentally stumbles onto his laboratory, and Dexter enlists him to repair the lab.
