Wikipedia: The Dalton School, originally called the Children's University School, is a private university-preparatory school on New York City's Upper East Side and a member of both the New York Interschool and the Ivy Preparatory School League. The school is located in three buildings, all in Manhattan: the Middle and High Schools for grades 4â12 are located at 108 East 89th Street; this building is referred to as simply The Dalton School or Big Dalton. Grades Kâ3 are taught at a different building on 53 East 91st Street; this area is known as The First Program or Little Dalton. The primary center for physical education and sports facilities is the Physical Education Center at 200 East 87th Street.