Honeymoon Island State Park is the setting for Island EarthDays 2008, a celebration held in honor of Earth Day. Among the diversions are the "Shark Bite Challenge," a four-mile recreational and eight-mile competitive canoe, kayak and paddleboard race, guided nature walks, interactive exhibits, eco-friendly craft vendors, a youth art show and children's activities, food, drink and live music throughout. April 19-20, 10 a.m.-6:30 p.m. Sat., 5 p.m. Sun., 1 Causeway Blvd., Dunedin, $5 entry per car (up to eight people), 727-738-2903, celebratewithfriends.com.