Collegiate School, a day school for boys, is the oldest independent school in the United States. Tracing its origins to 1628, the school was established by the Dutch West India Company and the Classis of Amsterdam, the parent ecclesiastical body of the Dutch Reformed Church for the colonists of New Amsterdam.

Beginning with Adam Roelantsen, twenty-eight headmasters have guided Collegiate "so that first of all in so wild a country, the youth be well taught and brought up." As New York City expanded to the north, the school moved from its original quarters on the southern tip of Manhattan Island to a number of different locations. In 1892 it settled at a site next to the West End Collegiate Church, where Collegiate took on its modern form as an all boys' school and continued to develop its college preparatory program. In 2018, the school moved from the site at 260 West 78th Street to its new home at 301 Freedom Place South.

Incorporated in 1940 as a non-profit organization under the Education Act of the State of New York, Collegiate School is no longer a church-directed institution, but the school maintains its historic association with the Collegiate Churches. A non-denominational school, Collegiate attracts a diverse group of boys, families, and faculty that has characterized the school for many years.