Franklin High School was a public high school in Franklin in Sussex County, in the U.S. state of New Jersey.
Known as Franklin Industrial School when it was first established, the school's first graduating class was in 1924, while the first regular class graduated four years later.
During an era when Sussex County had a limited number of high schools, Franklin High School at various points served students from Hamburg, Hardyston Township, Ogdensburg and Vernon Township in Sussex County and from Jefferson Township in Morris County In the face of "badly overcrowded conditions" at Franklin High School, voters approved a pair of referendums in November 1972 for the creation of Wallkill Valley Regional High School, while voters in Vernon approved the construction of a new high school for township students.
[1] Students from Vernon Township were given the option to complete their education in Franklin or switch over to Vernon Township High School when it opened in September 1975.
[2] For the 1978-79 school year, Ogdensburg withdrew from Franklin High School and began sending students to Sparta High School.