If you’re anything like Swedish pop artist Claes Oldenburg, it’s likely that you have an obsession with larger-than-life sculptures of mundane objects. If that’s the case, the Sacramento Zoo’s Earth Day Celebration is for you. The Earth-friendly event will feature an oversized, fabric hamburger that measures three feet in diameter and illustrates the amount of water required to grow the materials that make up one quarter-pound hamburger (it takes 698.5 gallons, for you inquiring minds). The burger, provided by the Department of Water Resources, will be on display along with other exhibits by various environmental groups from 9 a.m. to 4 p.m. this Saturday. Throughout the day, guests are invited to make chalk-art drawings, get their faces painted, create recycled-newspaper hats, visit the zoo’s wildlife wagons and go fishing for water-conservation tips. Admission is $7.25 for adults and $5 for children 12 and younger. The Sacramento Zoo is located at 3930 West Land Park Drive. Call (916) 264-5888 or visit www.saczoo.com for more information.