Croton-Harmon High School is a secondary school located in Croton-on-Hudson, New York. It is administered by the Croton-Harmon Union Free School District, and serves 9th-12th grade students. There were 542 students enrolled in the 2006-2007 school year. In the 2018-2019 school year, there were 506 students enrolled. Due to an increase in students since its original construction, it was expanded in the 1950s with a gym, and again in 2005/06 with eight new classrooms, an auxiliary gym, and a new library. Between 2006 and 2017, the library also included a space for students to use desktop computers. In 2017, the school received a grant for a Nureva Span system, which replaced the desktop computers in favor of a more collaborative learning support system.