Adelphi Academy (Brooklyn, New York, N.Y.)

Adelphi Academy is a prepatory school founded in 1863 by Dr. Edward S. Bunker and Aaron Chadwick, who had both previously taught at the Brooklyn Polytechnic Institute. Though the Academy made its start as a school for boys, it became coeducational in 1867. It was officially incorporated and chartered by the Board of Trustees of the City of Brooklyn in 1869, and grew steadily throughout the 19th century, reaching its peak enrollment of 1,291 students in 1891. The Academy's original location was at 412 Adelphi Street, but due to its steady growth, it gradually outgrew this space and moved to newly built facilities at the corner of Lafayette Avenue and St. James Place in 1868.

SInce as early as 1871, Adelphi Academy's administrators had considered the possibility of establishing a liberal arts college to be affiliated with the Academy. In 1896, under the administration Dr. Charles Herbert Levermore, Adelphi College (later, Adelphi University) was chartered by the State of New York. Its original location was in a building directly behind the Academy at the corner of St. James Place and Clifton Place. Though they operated as separate institutions, Adelphi Academy and Adelphi College remained closely connected, with many of the Academy's students matriculating to the College upon graduation.

In 1929, Adelphi College moved its campus to Garden City, Long Island and was granted university status by the State of New York in 1963. Due to steadily declining enrollment, Adelphi Academy moved from its location at Lafayette Avenue and St. James Place to a smaller facility in the Bay Ridge neighborhood of Brooklyn in 1965. As of 2010, both institutions continue to operate in the same locations.