The family is surprised when Alvin suddenly has a girlfriend, but quickly grow fond of her. Max however smells a rat and stands up for his best bud when he thinks this new love is just using Alvin for student government gain. Howie is testing the intelligence of a pig, but runs into trouble when the Ackermans keep treating it like a pet.
After Alvin claims not to have any fears, Max, Howie and Juliet set out to scare him. But with Diane and Abby away at a college interview, Lloyd is left in charge and does not know how to handle a potential ghost in the house.
Alvin and Juliet have been dating for a while and Juliet wants their parents to meet. But what seems like a harmless idea quickly escalates into the parents forbidding Alvin and Juliet from seeing each other anymore! At the same time, Max and Abby discover Howie has been keeping an amazing snow fort secret from them.
Alvin forgets an important anniversary with Juliet, then makes things worse when he tries to follow the not-so-sage love advice of everyone in the family. But eventually, with Abby's help, Alvin finds the confidence he needs to win back Juliet back. Meanwhile, Max meets his second biggest fan, Harley, and Howie's not happy about it.
When Max discovers that Alvin is secretly entering a battle of the bands to impress Juliet, he insists on joining his band! Abby comes up with an idea to keep the parents from missing her too much when she's away at college.
Abby is going away to college next year and realizes that she doesn't have any fun brother-sister memories of Alvin to take with her. So she sets out to create some new memories with him. Max undergoes a dramatic image change.
When Max's career aptitude test comes back inconclusive, he struggles to discover what he will do after snowboarding; Alvin tasks Howie with reprogramming Mr. P.
It's time for the huge, annual Blizzard Springs Science Fair - the town and Alvin are buzzing with excitement! At home, Lloyd becomes obsessed with beating Howie at her new board game, "Unicorns & Minotaurs."
Max wants to be the new school mascot, and Abby undergoes focus training for college.
Abby is frantic preparing for her last school dance, while the boys plan a double date they won't soon forget.
Abby gets stuck in an elaborate lie that even Max and Shred have to help her with.
Max worries when his career aptitude test comes back inconclusive. Abby convinces Max that he could make a good life coach. Max then offers advice to Abby, Diane, and Lloyd, which later backfires. Meanwhile, Alvin puts Howie in charge of reprogramming Mr. P so he will stop mocking him.
Alvin tries to sell his latest invention with the help of Max. Wendy Chong attempts to recruit Howie as a partner in science.