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 2005–2006 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.