This Saturday, community action and education organization Keep Hillsborough County Beautiful heads up a local incarnation of the 24th annual Great American Cleanup, a national Earth Day campaign for a cleaner, greener America. KHCB invites Bay area folks to become volunteers for several hours at any of the 32 Hillsborough County cleanup sites, including Apollo Beach Nature Preserve, Brooker Creek Headwaters, Courtney Campbell Causeway, Evans Park, Gardenville Recreation Center, Hillsborough Community College, Palm River Point Sheriff's Office and VISTA Gardens. Participants clear illegal dump sites, remove litter from streets, waterways and public spaces, plant trees and flowers at parks and schoolyards, take part in recycling drives and educational events, and plenty else. GAC volunteers receive free T-shirts, refreshments and restaurant coupons following the cleanup. Sat., April 19, 8:30 a.m.-noon. For a complete list of participating locations, visit khcbonline.org.