Mary-Kate and Ashley work as matchmakers to get Mrs. Baker and Mr. Fillmore together so that Carrie, a student of Kevin, will be hired as their new baby-sitter.

Kevin hires a tutor for Mary-Kate. Ashley convinces Mary-Kate to switch places so she can flirt with Taylor, the tutor, but their scheme doesn't go as planned; Carrie convinces Kevin to ask out a woman at a coffee shop.

Ashley becomes jealous when, during a slumber party, Mary-Kate reveals that she has kissed a boy; After Paul finds out Carrie was over at Kevin's he assumes their relationship is more than it actually is - which leads to rumors about them being a couple.

Ashley gets assigned Pokey Valentine, her crush, as a partner on a history project. She becomes jealous when Pokey and Mary-Kate begin spending time together.

When Kevin starts dating a woman, Marci, they fear that she will replace Carrie. The twins scheme to destroy Kevin and Marci's relationship.

Mary-Kate and Ashley switch costumes with Max and Brian so that they can attend Carrie's Halloween party, from which they were banned by Kevin.

Ashley is excited when a model search for a teen magazine takes place at their school, but Mary-Kate is chosen over Ashley.

Carrie's old boyfriend, Alex Reardon, is back in town and Carrie feels she must make herself look as successful as he is. Carrie convinces Kevin to pretend to be Carrie's fiance to make Alex jealous; The twins have a party which doesn't go quite as planned.