Wednesday, September 18, 6:30 p.m., Whitney Water Center: Estimation & Experimentation, North Haven Memorial Library. Free. For ages 6-10. Make estimates and then conduct experiments to see if the estimates are accurate. Some of the predictions made will include how many marbles will make a cup of water overflow and how many marbles will sink a boat. Registration is required. www.northhavenlibrary.net; 203-239-5803.