A boy named Tanner asks Keely out, but Phil doesn't really like him. One day when Phil is doing a skit on stage a girl named Darcy walks in and asks the teacher that if he sees Tanner to tell him that she stopped by. Phil thinks this is kind of weird, so, using his Instamorph, he changes into Tanner and goes to investigate. He finds out that Darcy is also Tanner's girlfriend and that he is two-timing Keely, but when he tells her she just gets mad at him. Later, while Keely and Tanner are doing a skit on stage Darcy walks in and kisses Tanner right in front of Keely! Meanwhile, Pim tries to get Debbie and Bradley to break-up.

Phil skips Unification Day to go to a party that he can't even get in to. Pim cheats on a cooking assignent, so she has to bake something homemade.

The Diffy's discover Curtis the Caveman stowed away in the time machine and now it's up to Lloyd to decide if they should keep him. Pim goes to Debbie's sleepover and tries to find a way out.

Lloyd and Barbara decide to go on a weekend road trip for their anniversery. They leave Phil in charge of Pim and if everything goes right then Phil will get an afterburner for his skyak. Once Pim hears this she is not happy and tries everything in her power to make the weekend go bad so Phil won't get the afterburner.

Phil is sent to second grade to work on his writing after he messes up on his cue cards for the news. Pim cheats on a test and her conscience bothers her.

Phil gets detention and goes to the dance with his new "guy friends." But when a bull attacks his new friend, he morphs it into a cat. Pim is tardy too many times, so she dresses Curtis up as her father to get off being punished.

Phil helps Keely with her stage fright so Phil shrinks himself and sits on her microphone during her performance; Pim and Bradley become co-parents of a bag of flour as part of a class assignment on raising a baby.

Phil and Pim worry that Lloyd will embarrass them when he plans to play American folk music at their school concert; Barbara takes Curtis to a dentist when he gets a toothache.

Phil tries to dissuade another girl's affections; Pim joins the orchestra to sabotage Debbie's solo; Pim meets Bradley Benjamin Farmer.

Pim and Phil start school in 2004. Phil meets Keely and offers to tutor her in Algebra. Pim tries to get through her first day of school.

Phil uses a futuristic gadget to compete in the gymnastics tournament.

Phil and Keely go to the Tomato Ranch. But Phil is worried about going in the tomato mashing tub as he only has 4 toes.

Phil and Keely start a day-care service for dogs to earn money for concert tickets. Phil uses a futuristic gadget to understand what a dog is saying.

A school video project causes Phil to overlook his friends' feelings; Pim is recruited for a track meet.

Debbie enlists everyone is school to help her bake cupcakes except Pim. But soon enough Pim is forced into giving the drum beat to the bakers. Phil and Keely try to help the helpless bakers.

Keely uses the "New-Ager" and pretends to be a substitute teacher, but she then gains the attraction of Mr. Hackett.

Phil tries to impress the mayor's daughter but things get bad when he switches places with Curtis. Pim realizes that she can't stand Debbie and doesn't even want to be her friend.

Phil defends Pim against a bully and then he gets bullied. Curtis takes the neighbor's lawn ornaments and calls them his "friends."

Phil and Keely enter a science fair featuring next Century's "milk engine" sending Lloyd into a state of panic that the Diffys will be discovered. Phil and Keely sneak into the fair to retrieve the evidence so the Diffys can remain in Pickford.

Phil and Keely pretend to be in cheerleading to impress Mrs. Teslow. Pim tries to find the one thing that Debbie can't stand.

Phil's future "friend" comes to 2121. He offers the Diffy's a way to get home. Will Phil choose the right decision?