Lola (Miley Cyrus) leads an ordinary life, with her boyfriend Chad (George Finn), and best friends Emily (Ashley Hinshaw), Janice (Lina Esco) and Kyle (Douglas Booth). When they return to school, Lola discovers that Chad has cheated on her over the summer, so the two of them break up. Lola and Kyle begin to realize that they have feelings for each other and pursue a relationship, but this is complicated due to the fact that Chad and Kyle are friends, and Lola's "enemy" Ashley (Ashley Greene) wants to date Kyle. Kyle and his band (which includes Chad) want to compete in the battle of the bands, but Kyle's dad doesn't support Kyle's passion for music and feels that it is getting in the way of his schoolwork. During the movie, Lola records all of these events in her diary.Lola's mom, Anne (Demi Moore), is a divorcee who frequently has sex with her ex-husband, Allen (Thomas Jane) until she finds out that Allen has been sleeping with another woman at the same time. Things between Anne & Lola are up and down. Anne is very protective of Lola. Lola spreads a rumor that she slept with someone, just to make Chad jealous who claimed to have had sex with Ashley. Anne finds out & confronts Lola, who denies it. Anne also begins to realize that she and Lola are growing further apart once Lola throws a party when Anne was away for the weekend with her ex-husband and is caught by Anne (who returns a day earlier), who threatens to not allow Lola to go on her class trip to Paris.Things finally start to change when Anne meets police officer James (Jay Hernandez) and they begin to date. During their relationship, James offers Anne advice on how to reconnect with Lola. She takes up the advice. After a presentation at school, Lola looks for Kyle in the bathroom, and overhears two people having sex in the stall. Lola assumes it is Kyle and Ashley after seeing a purse similar to Ashley's peeking out from under the stall. Lola confronts Ashley, who doesn't deny it. A huge fight breaks out between Kyle and Lola, where Lola accuses Kyle of cheating on her, and the two break up. After the breakup, Lola is determined to make Kyle jealous, and tries to do so by making out with her childhood friend Jeremy (Jean-Luc Bilodeau). Meanwhile, Lola and Anne reconnect (after James talks to Anne & tells her that she is good mother & Lola is a good girl), and Anne allows Lola to go on the class trip to Paris.Kyle's dad finds pot in the house & assumes it was Kyle who brought it. Coupled with his average grades, Kyle's dad is angry & breaks his guitar. While on the Paris trip, Emily finally admits to Lola it was actually her and her secret boyfriend Wen (Adam Sevani) in the bathroom, not Ashley and Kyle. After this realization, Lola and Kyle get back together and Lola spends the night with Kyle where he is staying, and they have sex for the first time. When they all get home, Lola sticks up for Ashley when Chad calls her a hoe. Ashley thanks her for this and it seems they could be friends again in the future.Meanwhile, Anne finds Lola's diary and finds out that Lola has slept with Kyle, made out with Emily and done drugs. She confronts Lola, and the two of them have a huge falling-out, causing Lola to move in with her dad. Eventually, Lola and Anne reconcile, and Lola moves back in with her mother. Kyle performs at the Battle of the bands without his dad's permission but leaves him an invitation. His dad attends & is impressed with Kyle's skills. Kyle's band wins battle of the bands with his father's support.Kyle and Lola stay together and Ashley and Chad begin to date. The film ends with Anne and Lola laughing out loud while cuddling.