Kimberly signs up Drea to run for student class president. She learns about telling the truth instead of lying to succeed in the election. Matt and Rebecca inadvertently ruin some of Dad's sheet music with finger paint, and then try to hide it to avoid punishment. In the secret adventure, Drea, Rebecca, and Matt are transformed respectively into a dolphin, an angelfish, and a puffer fish. They encounter a clown fish who pretends to be a shark, scaring the others. But when a real shark appears, it chases after the clown fish showing consequences for his lie, roughly equivalent to The Boy Who Cried Wolf.

Drea has plans to go shopping with Kim over the weekend but made a mistake on the dates. She has to babysit Rebecca, Matt, and their dog Floyd instead. Floyd is temperamental and wreaks havoc on the house, ruining an in-progress dining room renovation by Drea's parents. Floyd gets banished outside. Later, Matt notices Floyd has escaped and the trio, along with the help of George, go looking for him. In the process, Drea loses track of Matt and frantically looks for him. After he is found climbing in a tree, the trio go on a secret adventure, becoming dogs so they can "think" like Floyd and find him. In the scene, they rescue a baby who is in a runaway baby carriage. The baby's mother thanks them and they learn the value of being responsible and doing the right thing. Back in the real world, Matt then realizes where Floyd went, to his litter of puppies next door; Matt notes that Floyd has new responsibilities, being a dad.

Hampton Falls Junior High's extracurricular activities budget has been cut by the school district. Drea and her friends attempt various methods of raising the needed $10,000, but have little success. Drea attempts to ask Arlene's grandfather Duke to donate the money, but Arlene rebuffs her. Drea finally tries to win a local radio codebreaking contest to win the money for the school. Drea, Rebecca, and Matt go on a secret adventure where they learn the value of teamwork and cooperation to escape and capture a leopard as respective jungle animals: a giraffe, an elephant, and a monkey. After the radio show gives out the final clue, the whole Thomas family, along with Duke, who is one of Grandpa's old school friends, work together to come up with the code word, which happens to be "Teamwork," but another caller gives the correct answer first. Later at school, Duke decides to donate the $10,000 to the school and makes a pledge to match any money raised by Arlene and Drea together.

In the fall, Drea is attempting to grow pumpkins in the garden, but they are quite misshapen and small. Drea is disappointed, but Grandpa suggests they should be cooked into a pumpkin pie. Drea is waiting for a decision on her joining an Environmental Society internship. George competes for that same spot and ultimately is chosen, to Drea's chagrin. She also wants to go to the Billy Holden concert but is unable to get tickets further discouraging her. In the meantime, Mom experiences self-doubt after she loses her corporate job at Jamison's. Matt is learning karate but was beat up by a girl at school embarrassing him. Drea, Rebecca, and Matt go on a secret adventure as skunks. They encounter a fox being chased by hounds in a foxhunt. They are cornered by a cliff but the trio figure out how to solve their problem, by spraying the dogs with their stinky liquid. They learn that everyone has a purpose, even animals who are very stinky.

At Christmastime, the Thomas family decides to only buy one special gift for each other. Drea also buys a special gift for her rival Arlene. Meanwhile, the Mrs. Long tells her children that there will be fewer gifts this year due to financial constraints, and the children come to terms with it. Drea, Rebecca, and Matt go on a secret adventure, as mice. They meet a poor cockney mouse who invites them to share in their Christmas dinner. The trio learn the value of giving and how people can be happy even without material possessions.

Drea and Kim try out for the school basketball team, but Drea has doubts she can make the cut. After a first day of tryouts go poorly, Drea plans on quitting. Her parents train with her and encourage her to keep going. Meanwhile, Rebecca and Matt are trying to come up with a topic for a recycling project for school, and Dad is experiencing writer's block in his latest composition. The next day, Drea goes to the second day of tryouts, a scrimmage match between all the prospective players. She scores the winning three-pointer and makes the team. Rebecca and Matt come up with the idea for their school project and Dad's new composition: musical instruments made out of recycled trash.

Drea's Dad gets a job offer to teach music at the "California University." (Probably analogous to UCLA.) The Thomas' travel to Los Angeles for Jim's final interview and to get to know the city. In preparation for Drea's cross-country move, Rebecca and Matt now have Arlene as babysitter. They go on a secret adventure as caterpillars who turn into butterflies, showing how loss and sacrifice is necessary for beneficial change to occur. George also visits Drea, clearly upset at her moving, and kisses Drea. Grandpa tells Jim that he can't give up his life in Hampton Falls and won't go with the family to the west coast. Jim later tells the family his decision, impressed with all their sacrifices for his career. He decides to turn down the offer and they stay in New Jersey.