Joel is failing in Biology and his parents think he needs a tutor, who happens to be very attractive. Joel works hard to impress his tutor, Abby, so that he can ask her out on a date. The two start to spend more time together after Abby's boyfriend dumps her. Joel gives her advice about how to get over her breakup, hinting that she should take him out. When she does invite him (after she is no longer tutoring him due to Joel going so well in Biology) to see a movie he is shocked to see that she has also invited her ex because of Joel's advice. Later, Joel tracks down Abby to tell her that she is doing the wrong thing but changes his mind after seeing that she is too "old" for him, he then goes to tell her boyfriend to treat her right. Meanwhile, Pat believes (because of Joel's vague prediction) that he and Isabelle will both break their virginity together. He tires as hard as he can to impress her, with failed results.

Joel Larsen competes in the science fair in order to not flunk the class. He tries to ride the coat-tails of Andrew Wages, a brainy science kid who supposedly invents the technology for satellite TV in the future and owns millions. The side-story is about the Larsen family coming together after Joel helps them steal cable TV from the Nachman's.

"It's all about timing", is Joel's motto as he uses his second chance in life to ask Holly Kent to the Valentine's Day dance. Well, that and a red rubber ball, as we later discover as he seizes his moment during a game of Dodgeball, when he steals the woman of his dreams from possessive Gary Ross. Joel also tells his best friend that the girl who said at her High School 10-year-reunion that she always fancied Pat, was a girl called Stacey and so they pair off also. Isabelle finds her man in Todd York with whom she was last seen in a bitter argument at their Model U.N. Conference. When it comes to the crunch during the main dance, Joel is torn between staying linked with Holly, and persuading his parents, who came along as chaperones, that they should be dancing together rather than his father throwing his marriage into the toilet by insisting that Saturday night is always "Poker Night". Which way will he choose?

When Joel's mother comes up with the idea of tying string around the top of a trash bag, which he labels "Synch-sacks", Joel figures it's high time his father actually took her inventions seriously. Joel chooses his time carefully, opting for scaring the man half to death during his first driving lesson, given that he now has 20 years of driving experience behind him. Bill finally relents, but the disaster that unfolds is "Chilghetti", a mix of chili and spaghetti. It's not available in the 21st century, so compared to the other inspirations she's had, this one surely can't be a winner? Meanwhile, Isabelle is set for a disaster of her own as she plans to audition for Scarlett O'Hara in a school production of "Gone With The Wind". Joel has knowledge about the audition which, unless it's stopped, will make for a moment that will haunt her until the end of her school days. At the end as the family go ahead and begin to put Chilghetti on the market, they make a toast to an uncertain future. If only this show had had a future.

Joel is thrust back 20 years into the past, where his first order of business is to survive algebra class and keep from being humiliated in the student council election.

Joel picks a fight with a high school bully. This time around, he decides to stand up for himself.

Tired of not having money, Joel decides to get a job by selling paper. Something his future self used to do.

Joel makes desperate attempts to call his father's attention on his wedding anniversary and try to make him give his mother more attention, because the man who broke up their marriage and later married his mom is just starting to put moves on her. He makes a romantic dinner for his parents with old home movies from their engagement party and makes his father invade her private ceramic lesson to stop anything from happening between his wife and the teacher, but all he finds is an unfinished cigar holder she was making him. Joel saved his parents marriage, but can he explain why he was hanging out in a bar with his sister after she made fake IDs for them?

Joel is faced with re-living one of the most embarrassing moments of his life: when he made his baseball team lose the game after missing 3 balls. He tries his best to avoid playing at the game, but his efforts are useless. He will have to see his dad yell at him, his mother run away with shame, his sister call him a dork, Holly Kent laugh at him and worse: this time his grandpa, Isabelle (who's having a bad hair week thanks to a bad perm) and TV are there. Joel misses the balls, but instead of running home like before he stays and faces everybody. Turns out his dad was yelling at someone else, his mother just went to pick up sodas from the car, Holly Kent was laughing at some dogs and his sister was really calling him a dork. Facing his failure isn't so bad after all, especially when you discover you were the one who gave Greg Maddux confidence to carry on with his future brilliant baseball career. Pat, on the other hand, isn't so lucky and has gets his wrist broken like before.

Pat makes Joel steal his dad's precious Cadillac and go to the Def Leopard concert so they wouldn't be stuck home "with only three networks". At the concert, Joel uses his smooth talk to buy tickets from a scalper for him, Pat, Isabelle and Holly Kent, who he met at the parking lot waiting outside for her date to come out of the concert. Just as they are about to get in, Joel changes his mind and rescues his sister from the most humiliating night of her life. Unfortunately, he is caught red handed and his parents decide to act tougher on him – thanks to melancholic, depressive poem he wrote in English class entitled "Smells Like Teen Spirit" – and Cheryl doesn't remember a thing the morning after.

It's Halloween, and Joel has a chance to rewrite what was his first kiss, which he accidentally had with Bonnie, an annoying girl who would end up dating him against his will for 6 months after that. How surprised is Joel when he sees Bonnie at the party she was not supposed to be at, thanks to an invitation made by Pat. In a desperate moment, Joel kisses Isabelle, and convinces her to pretend she's his girlfriend for the night. When he sees Holly Kent break up with her boyfriend of the week, Joel quickly dumps Isabelle, who gets hurt. Joel finally has the opportunity of a lifetime when Holly asks for a kiss, but chooses not to do that when he sees she'd only be doing that to cause jealousy on her boyfriend. They go home and start cleaning the t.p.'s that are all over the Larsen home, since they are "the raisins house" (while Bill and Karen get things heated up in the backyard with Tarzan and Jane costumes), leaving Pat making out with Bonnie and Cheryl trading one loser for a guy who would eventually become a famous cardiologist, if it wasn't for her influence.

When Joel enters a Star Search-like competition using a hit song from the future, he reevaluates whether he should become an accomplished musician the honest way or by stealing someone else's material..

When Joel has the opportunity to change the events of the street block party where his family was ostracized by the neighbors, he tries to teach his father that winning isn't everything. Meanwhile, Joel also attempts to protect Isabelle from having her heart broken.

After butting heads with his father over his curfew, school trips and adult responsibilities, Joel decides to stand up for himself and moves into Pat's home where the rules are more liberal.

Joel decides he is not going to let turning 15 get in the way of celebrating what should be his 35th birthday, and cuts school with his friends Pat and Isabelle.