The book starts in Mr. Myner's classroom. Mr. Myner is telling the class about Lake Placid, the girls and boys both get to go there for three days! But the only thing that so cute is that all Pretty Committee really cares about are the boys. At the end of the class, Kristen Gregory starts crying because she can't go; her parents won't pay the $ 1,500 fee. Alicia, Dylan, and Massie offer to pay, but Kristen does not take the offer. When the PC is waiting on the sidewalk to get picked up, they overhear Livvy Collins, Alexandra Regan, and Carrie Randolph gossiping about Nina Callas. They wish that she was here because they want "boy tips" from her; at Lake Placid, they'll be spending a lot of time with the boys. Massie lies about her kissing experience and tells them that she's started a kissing clinic called MUCK. Livvy, Alexandra, and Carrie all join; along with Dylan and Alicia who also believe Massie's kissing fib. Claire is the only one who knows that Massie hasn't kissed anybody except for her father, but plays along anyway.
Claire confesses to Layne Abeley that she kissed Josh Hotz, and why Cam dumped her. She's moping around and mourning for Cam. Layne suggests that she give Claire bangs to get her "Disney charm" look back. Claire reluctantly agrees, only because she thinks that it'll take her mind off Cam for a moment. But while Layne is cutting Claire's hair, Todd Lyons and his ugly loser dog Aibo burst in, startling Layne and ruining Claire's hair. Claire is so desperate for Cam that she writes Cam a poem.
Massie hosts her first kissing lesson at OCD's chapel. The kissing lesson was a failure, and Massie abruptly stops it with a warning "phone call". They board the luxury bus to Lake Placid. At last moment, Dylan's mom, Merri Lee Marvil tags along. Massie feels uncomfortable around her crush, Derrington, who she has to sit next to for the six hour bus ride.
At Lake Placid, Mr. Myner confiscates all electronics, food, and excess clothes as he tries to get them to start "living light". Massie's Pretty Committee Lake Placid Packing List has been a waste! Their stay at Lake Placid, Merri Lee flirts with Mr. Myner. Claire mourns for Cam and dreads the day Alicia will find out that she kissed her crush. Massie asks Claire to give her kissing lessons, so she can fake her experience to the MUCK girls. In exchange, Massie will find a way to get Cam back for Claire. Massie sets up Mr. Myner's igloo for her next MUCK class. Before it starts, Claire pops in and gives Massie a kissing lesson. Massie repeats the same kissing lesson in front of the MUCK girls. This time, the lesson was a success. Derrington hears about Massie having kissing experience and thinks that Massie is cheating on him. He dumps Massie and throws away her "M" brooch. The MUCK girls storm off, thinking that Massie is a desperate fraud.
Kristen turns up, she sneaks away from home and is at Lake Placid without permission. She hides under Massie's bed and eats what the girls give her. She spends hours memorizing trail maps. Dressed as a boy, Claire sneaks into Cam's cabin and apologizes. Cam forgives her and tells her to meet him at seven o'clock at Powwow Log. Claire agrees and leaves, but Alicia overhears their conversation. Derrington thought Massie was over him so he breaks up with her. Massies end up kissing Derrington the second time on the ground (while MUCK girls watched) and told him that she still likes him and just wants their relationship to be more private. Massie receives another kiss from Derrington and regains her title as an experienced kisser, and the MUCK girls apologize.
Due to a confusion, Cam ends up almost kissing Alicia because Alicia wanted to get revenge on Claire for kissing Josh. Claire runs away crying but forgives Cam when he sneaks into the girl's cabin and apologizes. There, they share their first kiss. To get revenge, Claire blames the dirty underwear on Alicia.
Dylan gets upset because Merri Lee and Mr. Myner are snuggling on the couch. Kristen gets exposed, and she and Dylan run out into the woods. Massie, Claire, and Alicia go after them. All five of them end up getting lost in the woods for hours. They even confront a bear and when they finally turn up, they find an angry Mr. Myner waiting for them. Mr. Myner expels all five of them. The last scene is Derrington handing Massie wildflowers, and Massie announces to the students that they've been expelled.
The Clique Gone Wild
Massie Block: The girls of Octavian Country Day School pack up their warmest cashmere coats and their tiniest iPods and board the bus for a Presidents' Day class trip to Lake Placid. But bears aren't the only scary thing out in those woods. The Briarwood Boys are staying in a cabin just a few yards away, which means the girls in Massie's Underground Clinic for Kissing (M.U.C.K) might have to find the guts to put their money where their well-glossed mouths are.
Kristen Gregory: Can't afford to go on the trip. Will she rot in Westchester all alone? Not likely!
Dylan Marvil: Finally skinny after a bad bout of the flu. Will she stay skinny when she sees her mom smooching it up with her history teacher. Cause that's enough to make anyone yak!
Claire Lyons: Gets a crazy haircut and a bloodthirsty new enemy, but none of this matters since Cam has taken his heart (and his gummies) away from her. She'll do whatever it takes to get him back....
The Clique... the only thing harder than getting in is staying in.