This could have been unrelentingly terrible, but is actually pretty fabulous. Raised and home-schooled in Africa, perky protagonist Cady (Lindsay Lohan, nicely restrained) enters suburban high school blissfully unaware of cliques, but soon joins the nasty, "Heathers-lite" Plastics (Rachel McAdams, Amanda Seyfried, Lacey Chabert). Battles of identity and territory ensue, involving friendly art fags (Lizzy Caplan, Daniel Franzese), an adorably daffy math teacher (aptly surnamed screenwriter Tina Fey), and a righteous principal (Tim Meadows, hilariously deadpan). With a wink at John Hughes and a Band-Aid for Columbine, this loose adaptation of Rosalind Wiseman's nonfiction book Queen Bees and Wannabes bellyflops into the American high school experience with a healthy reservoir of wit. Credit Fey as well as director Mark Waters (the fun Freaky Friday remake, The House of Yes) for festooning their teen flick with strings of knowing giggles for the over-18 crowd. What could have withered into a feature-length detention ends up feeling like a homecoming ball.