In 1821, Boston started the first public high school in the United States. By the close of the 19th century, public secondary schools began to outnumber private ones. Over the years, Americans have been influenced by a number of European reformers; among them Pestalozzi, Herbart, and Montessori.oston Latin School was founded in 1635 and is both the first public school and oldest existing school in the United States. The first tax-supported public school was in Dedham, Massachusetts, and was run by Rev. Ralph Wheelock.