Lenny Clarke lent a hand at this weekend’s enormous Pinewood Derby hosted by the Boy Scouts Boston Minuteman Council. The 335½ -foot track set up along the Charles River broke the world record, according to the gang from Guinness which was on hand to verify. (More than 5,000 boys and their families took part in the event.) Clarke is currently shooting “Clear History’’ along with Larry David, Jon Hamm, and Kate Hudson. He plays one of David’s poker buddies on Martha’s Vineyard, which just happens to be where Clarke and his wife, renowned fishing captain Jennifer Miller, reside.