Once again Anna Faris, the only reason to see the Scary Movie franchise, adds undeserved riches to an awful premise. As Shelley, a former Playboy plaything booted from Hef's mansion because she’s too old, Faris spends much of the film in skimpy two-piece outfits. Shelley winds up as a sorority-house mother to a bunch of dweeby losers — Emma Stone, Katharine McPhee, Kat Dennings, and Rumer Willis among them — about to lose their charge because they can’t attract new members. Cheap gags à la Revenge of the Nerds and Animal House along with the requisite T&A fall like dollar bills at a strip club. Faris nonetheless pushes a ditzy can-do that’s part Pam Anderson and part Drew Barrymore and manages to kindle warmth and even humor — no thanks to the jerky direction by Fred Wolf. Be sure to look for the progeny of Bruce Willis and Tom Hanks and a Cheetah Girl cameo. 97 minutes | Boston Common + Fenway + Fresh Pond + Circle + Suburbs