Camille lives with her overworked single mother whom she views as a neglectful parent, while her older brother has recently come home from being overseas fighting in the War in Afghanistan.

At a party that weekend, Camille speaks with the father of her baby for the first time since their sexual encounter, and she agrees to allow him to assume no parental responsibilities once the child is born, later confiding in Julia about the conversation.

Soon afterwards, Julia and Flavie both discover that they are pregnant, causing controversy at their school as faculty members attempt to brainstorm ways to combat the increasing amount of teenage pregnancies amongst their students.

Meanwhile, Clémentine's parents respond aggressively to discovering that she is pregnant, and with the help of Camille and the other girls, she runs away to live in an abandoned mobile home in Étel where they intend to establish their commune.

Première likened 17 Girls to The Virgin Suicides by Sofia Coppola saying "same languid pop, same delicately grainy picture, same kind of heterogeneous female cast, same absence of boys, reduced to the roles of stooges".