After Barbie, Tia and Courtney have band practice, they go to a tabing-dagat with their friend Kevin, who loves to make films. It is the last araw before their sophomore taon at high school begins, so, at sunset, they each make a wish for the new school year: Barbie wishes to anchor the school news channel; Courtney wishes to improve her drumming; and Tia wishes to be class president, but Kevin refuses to say his wish out loud. The susunod day, Barbie drives to school with Courtney and Tia, but her ex-best friend Raquelle steals their parking space.

In school, Barbie is distracted sa pamamagitan ng her crush Todd, a jock who is dating Raquelle. Todd and Raquelle go to a lawn where the popular kids hang out, and Barbie imagines being popular like them. Raquelle teases Barbie for watching Todd, and Barbie mentions to her mga kaibigan that she and Raquelle used to be mga kaibigan before Raquelle became popular.

Barbie goes to talk to Mr. Wexler for a news anchor audition, but Raquelle auditions too. Raquelle gets the anchor position and Barbie only gets to be her assistant. Later, Kevin phones Barbie to tell her and her two friends, Tia and Courtney, to come to the front of their school, and they quickly meet up with him. Kevin shows Barbie and her mga kaibigan a video of Todd and Raquelle having a fight and breaking up, so when Barbie sees Todd again, she comforts him.

Kevin films Tia's class president campaign, and Barbie and Todd become mga kaibigan and he drives her home. Barbie and Kevin later have a movie night together, and he tells Barbie to co-anchor with Raquelle. Barbie asked Mr Wexler if she could co-anchor, but he would only agree if she had a good enough story. Todd comes to see Barbie, but Raquelle wants him to leave.

Barbie's mga kaibigan are happy that she and Todd are mga kaibigan and say they could go to the Fall Formal — the school dance — together. Todd asks Barbie to watch him at football practice, and, as Todd pays madami attention to Barbie, it annoys Raquelle. Barbie goes to the mall with Tia and Courtney to get an outfit for the Fall Formal, but Todd phones Barbie to tell her he is dating Raquelle again. Raquelle, who was also shopping in the same store with her friends, Regen and Dawn, picks on Barbie. A tindahan assistant, Stephanie, who witnesses this, feels sorry for Barbie and gives her a free bracelet and diary.

Barbie feels humiliated the susunod araw at school and writes in her diary. She later drops her bracelet, and when she finds it she also sees a poster for Fall Formal band auditions. She signs up her band, Charmz, that she is in with Tia and Courtney. Barbie later tells Kevin that all Raquelle cares about it being popular, not the news. This gives Barbie an idea to study what makes popular students different from unpopular students.

Kevin brings Barbie a camera for her study. Courtney and Tia see, sa pamamagitan ng the way Kevin looks at Barbie, that he has a crush on her. Kevin doesn't want to tell Barbie his feelings because she already has a crush on Todd. At school, Tia and Courtney witness Todd and Raquelle having an argument. Barbie shows Tia and Courtney a lip gloss disguised as a text highlighter.

Barbie goes to her locker at gets a note from a secret admirer. Courtney and Tia know it's Kevin, but Barbie doesn't. Barbie is asked to make lipstick highlighters sa pamamagitan ng other students, and Regen and Dawn invite Barbie to hang out with them instead of Tia and Courtney. Barbie agrees, but says it is only for her study. Kevin later asks Barbie about her secret admirer, and she thinks it is Todd. Raquelle tells Regen and Dawn not to hang out with Barbie, but they ignore her and spent time with Barbie anyway.

Raquelle tries to make Barbie miserable, but Barbie ignores her. She stills gets secret admirer letters, and the latest one says she will see her admirer at lunch. She does, when she sits with Kevin, but she still thinks it's Todd because he walked past her table. Charmz do their Fall Formal audition, but afterwards, the principal gives them detention because of Barbie's lip gloss highlighters. Tia and Courtney were angry with Barbie because of this, but they cheered up when it was announced that they would be performing at the Fall Formal.

Barbie thinks that her luck is because of the diary. She realises that everything she wrote in her diary came true. Barbie goes back to the store to talk to Stephanie, but the only store assistant doesn't know who Stephanie is. She looks strikingly similar to Stephanie, however much older. At school, Barbie and Courtney help Tia put up fliers for her class president campaign. They are also helping her do a rally at lunch. Barbie gets another letter from her admirer and she says she will tell Regen and Dawn she is getting pag-ibig notes from Todd while he is dating Raquelle. She figures that if she tells Dawn and Regan they will begin to trust her more, thus improving her story. Tia and Courtney are unsure of this because they know it's Kevin, but Barbie goes to the popular lawn to tell them instead of doing Tia's rally.

As Barbie becomes madami popular, she begins hanging out with Regen and Dawn for real, and gossiping about them behind their backs. Tia an Courtney realise that Barbie would rather be popular and do her study that rehearse with Charmz, but Kevin shows Tia and Courtney their teaser to Mr. Wexler to prove Barbie is just acting. While Barbie sits with Regen and Dawn on the popular lawn, they told her to talk to Todd about the secret admirer letters.

Barbie shows Mr. Wexler her study film and he wants her to anchor it live on Friday night. At a band rehearsal, Barbie and her mga kaibigan celebrate Barbie getting to anchor. Barbie thanks them for being patient but Regen and Dawn confront Barbie for using them. Raquelle and her mga kaibigan pick on Barbie, and Raquelle steals Barbie's bracelet after finding out Todd might be sending Barbie secret notes.

Kevin shows Courtney and Tia the film Barbie will broadcast, but they find out she gossiped and spread rumors about them. They confront Barbie, and she explains herself but they don't want to be her friend or do the Fall Formal any more. When Barbie anchors her story, Tia and Courtney watch anyway. Barbie decides to not to ipakita her film, and instead shows one of Kevin's films. She apologises to her mga kaibigan and they forgive her, and agree to perform at the Fall Formal.

Barbie is sad that she Nawawala her bracelet, but Kevin comforts her and she grows madami confident with herself. She and her mga kaibigan go to the Fall Formal and Charmz performs. Raquelle tells Todd to leave with her, but he ignores her and later dances with Barbie. Barbie mentions the secret notes, but when he says he didn't write them, she realises Kevin was her secret admirer. She dances with Kevin and he gives her the bracelet Raquelle stole, which he found on the floor after Raquelle left. At the end of the movie, they have a movie night together.