Think your toddler has what it takes to win a 50-foot dash? Then enter the Diaper Derby and find out. During the race, parents do all they can to coax crawling toddlers across the finish line. Theres always one or two that take off for the finish line, said Carolyn Schuster, managing director of the Yarmouth Chamber of Commerce and festival co-organizer. They go, go, go and they get within 10 inches and they stop. Its so much fun to watch. Same goes for the Maine State Clam Shucking Contest. The events are all part of the packed, fun-for-all-ages schedule that also includes a parade, road races, and firefighters muster competition. And, of course, you can get clams every way imaginable. 162 Main St., 207-846-3984, www.clamfestival.com; July 15-17; check website for daily events, free.