333 W. Broad St., Franklinton
COSI comfortably beat out last year's winner, Columbus Museum of Art, proving it's not just for kids. The 320,000-square-foot mega-museum houses all the fun (and science) you can pack into one day. And who doesn't love a competitive game of rat basketball? COSI's current exhibit, "Grossology: The (Impolite) Science of the Human Body," may seem slightly juvenile, but you'll probably learn more than you'd expect. Next month, COSI's most visited centerpiece, "Titanic: The Artifact Exhibition," returns with full-room recreations, authentic treasures and 100 new artifacts.
Runners-up: Columbus Museum of Art, Wexner Center for the Arts