Thomas Jefferson High School was an all-boys public high school in Elizabeth, in Union County, New Jersey, United States, which operated as part of the Elizabeth Public Schools. The school opened in 1929 at which time Battin High School became an all-girls school. The school operated on a single-sex basis for 48 years until the end of the 1976–77 school year, ending its status as one half of the state's only pair of public high schools operated separately for male and female students.
In 1977, district officials stated that the inability to determine attendance zones for the two comprehensive high schools after Thomas Jefferson High School opened in 1929 combined with the expansive shop facilities in the new building, led the district to decide to split students by sex, with girls at Battin and boys at Thomas Jefferson.
The school closed at the end of the 1976–77 school year, after the Elizabeth High School complex was completed and all of the district's students, male and female, were accommodated at the new four-building facility, ending the city's status as "the only community in the state with separate public high schools for boys and girls". The $29.3 million project included renovations to Thomas Jefferson High School, which was integrated into the new complex. The Battin High School building, together with the four existing junior high schools, was repurposed as a middle school for grades six through eight.