Olsen makes a splashy style statement at the American Museum of Natural History in N.Y.C. Plus: Paris & Benji, Will Smith, Cameron Diaz and more

WORKING GIRL

Lauren Conrad makes waves on the runway after debuting her fall collection Tuesday at Smashbox Studios in Culver City, Calif., as part of Mercedes-Benz Fashion Week. "I wanted to stick to my California roots," the Hills star told PEOPLE before the show. "It's a great time because I get to take all of my months and months of work and display it for everyone and celebrate what I did. It's where the work pays off."