Stacy Friedman has just had the most awesome summer of her life. At camp, she and her best friend, Lydia, met a girl who trained them in all things cool, like how many black plastic jelly bracelets to wear and which teeth-whitening strips work the best. Equipped with this new knowledge, they're set to make an unforgettable back-to-school debut.

Unfortunately, Stacy and Lydia aren't the ones turning heads at Jefferson Junior High. Their clothes, makeup, and hair are totally wrong. Instead, everyone clamors around their other best friend, Kelly, who has transformed from not so cool to so very cool inthree months. Stacy and Lydia are happy for her, but shocked when Kelly gets super cozy with Kym and her popular clique, the Chicas. Worst of all, Stacy and Lydia are the only ones NOT invited to Eben's Hollywood-themed bar mitzvah.

But Stacy refuses to accept their social blacklisting. So she decides they should crash Eben's bar mitzvah. Though they risk being reduced to a Marni Gross-level of popularity, it is the only way to reclaim their status as eighth-grade It girls. Before the party ends, Stacy and Lydia will have gone undercover, posed for paparazzi, and faced off with the Chicas. They'll also find out exactly who their true friends are.and aren't.