The Children's Museum of Manhattan on the Upper West Side is five floors of artistic and educational activities for children ages 1 to 7.  From painting workshops to storytelling groups, this is the perfect space for those tourists with very young children; there's even a soft play space for babies.  Activities vary with the seasons-the holidays are a great time to visit-and warm weather will bring the kids outside to float boats and play with talking dragons.  Admission is 11USD (and free from 5-8 pm the first Friday of every month).

cmom.org