When Dee Dee tries to cut off a piece of her hair, she accidentally cuts off one of her pigtails. Dexter gives her a potion to make her missing hair grow back. However, Dee Dee squirts too much of it in her hair, and Dexter must return Dee Dee’s hair back to normal.

Dexter is forced to take Dee Dee to the zoo. There, she ends up trying to save an ostrich with disastrous results. Dee Dee and the ostrich switches their places.

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

When Dexter uses anti-matter on the family car to shorten road trips, he accidentally fuses Dee Dee with the car.

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

Dexter’s school and parents decide to send him to college. He ignores his fellow students, who prefer to “party now, study later”, until his mind finally snaps from the workload.

Dexter’s parents remember their first date and dance together.

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.

In need of an assistant to operate his latest invention, Dexter performs a brain transplant on Dee Dee to make her smart enough to fulfill the role. With her new brain, Dee Dee proves to be more intelligent than Dexter.

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.

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.

Major Glory forces Krunk and Valhallen to tidy up their apartment for his Uncle Sam, who is coming over for a visit.

Since his studying is interrupting his favorite TV shows, Dexter creates a helmet to absorb the shows directly. However, the plan backfires when he randomly snaps into television-based outrages.

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

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

After Dee Dee declares that she can beat Dexter in any game, Dexter challenges her to a series of games in his lab, though he prefers to win by cheating.

To keep himself from forgetting anything important, Dexter uses a device to copy his memories, which causes a mayhem in his own head.

Dexter creates a magnetic field to keep Dee Dee away from him, but it malfunctions, causing them to stick together.

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

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

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.

Dexter catches the chicken pox, and Dee Dee tells him a ridiculous tale that if he keeps scratching them, he will turn into an evil chicken. Dexter completely restrains himself so that he will not have to scratch it; unfortunately, he is unable to resist and his nonstop scratching eventually does just that.

During a trip to Japan as part of a student exchange program, Dexter accidentally releases a giant monster with an axe-like head from a volcano, forcing him to enlist the aid of his family to defeat it.

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.