Barbie, Tammy and all of Golden Beach High team up to defeat their rivals, Empire Coast High—which tests Tammy's loyalties due to them being her former school.

On Halloween, after watching a scary vampire film, Chelsea and Stacie come to believe that Barbie and her friends are all vampires, when in fact they are trying to set up the Dreamhouse into a haunted house.

When the Roberts go on their annual camping trip, Barbie makes brownies that no one can resist, but forbids anyone from eating them until the second night around the campfire, per family tradition. When someone eats the entire batch the night before though, the Roberts clan band together to figure out "whodunit".

After the Roberts camper is totaled after rolling down a hill, to raise the money to replace it, Barbie and her sisters sign up to compete in a game show that is infamous for tearing families down.

Barbie feels horrible when outside commitments keep her from taking Chelsea to her first circus, so Barbie decides to make up for it by putting on a circus at the Dreamhouse.

The Dudes & Trey get into a fight that results in the Dudes befriending Barbie instead. Without the Dudes, Trey finds a friend in Ken when they bond over a video game.

To gain more popularity in school, Tammy decides to imitate Barbie. When it goes too far, Barbie begins to feel deprived of her individuality. Meanwhile, Trey struggles to find a birthday gift for his mother, while Stacie and Chelsea agree to babysit a fashionable macaw named Bella, and end up losing her. Their problems intersect when Bella lands up at the Reardons' home, and Trey's mother, mistaking it for Trey's gift, falls in love with her. How will the Roberts sisters retrieve her?

Just before a group chemistry project presentation, Barbie falls ill with a cold. However, she does not want to take a day off and tries to figure out some way to attend the presentation without letting her project partners down. Meanwhile, Trey fakes an illness to play hooky, but runs into trouble when the principal catches him out of school.