Mia tries to make friends with Olivia, the new girl, but when Olivia makes fun of the other Cupcake Club girls and tells Mia she shouldn't hang out with them, Mia must make a decision about her new friendship.

There's a new girl in town, and Mia tries to take her under her wing. But Olivia Allen is not so nice; as a matter of fact she might be even meaner than Sydney Whitman! She asks Mia to lend her money, and even though Mia has been saving for weeks for a new pair of shoes, Mia lends it to her, only to find out that Olivia has used the money to buy the exact same shoes Mia has been saving up for! Plus she makes fun of the other Cupcake girls and tells Mia she shouldn't be friends with them. Will she wreak havoc on the Cupcake Club before Mia sees her true colours?

Mia learns to balance style and substance when she has to get glasses AND braces. Fashionista Mia gets some unflattering news from Katie’s mom, Dr. Brown: She needs braces. And just when Mia thinks things can’t get any worse...they do. Her teacher is concerned that Mia is squinting in class. A trip to the opthamologist confirms it: Mia needs glasses, too! Mia is miserable until her stylish mom comes to the rescue with a plan and a very chic middle school look. And her wonderful Cupcake Club friends reassure her that glasses and braces don’t get in the way of all they really see: the same old Mia.

Katie thinks things might get back to normal and then Callie announces that the Popular Girls Club is baking cupcakes for a fund-raiser at school.

When Emma is successful while modeling in an advertisement, she realizes it is a lot tougher than she thought.

Katie needs the help of her friends to cope with the changes of her mother getting a boyfriend and when she gets an e-mail from her dad saying that he wants to meet her.

Alexis has true friends in the Cupcake Club—which is a good thing, because everyone else is calling her names. Everyone in the Cupcake Club was thrilled when mean girl Sydney moved away, but the new girl, Olivia, is even worse than Sydney was! Every time she passes Alexis in the hallway, she says something nasty to her. And if that wasn’t bad enough, she also has all the girls in the Best Friends Club making jokes about Alexis! Alexis has no idea why this is happening...until she remembers an offhand remark she made to a friend about Olivia. It wasn’t meant to be mean, but did Olivia take it the wrong way? If Alexis is willing to shoulder some blame, will Olivia call off the teasing campaign?