The New Jersey Children's Museum was featured as one of the "50 Best Places To Take Kids in New York City" (City and Co 1998). Although they are located in N.J., they are so close (15 minutes from the George Washington Bridge) and so great for little kids that the editors made a geographical exception for them. They have special programs for school groups and are available for birthday parties.
"Your family will have hours of fun playing and learning together! The Museum has over thirty different exhibits, in 15,000 square feet, each designed for specific groups, from the special Baby Nook and Housekeeping for two's and toddlers, to the challenging Science and Technology for first graders."