East Brunswick High School opened for the 1958–59 school year. Previously, students living in the Township had attended South River High School in neighboring South River. In that first year, the school housed grades six, seven, eight and nine. Those four classes occupied the school until June 1962, when the original 9th graders became its first graduating class and the school contained grades nine through twelve. Because the school exceeded its intended capacity of 1,700 students, freshmen were dropped into the town's two junior high schools in 1967, later one junior high school. Enrollment reached a peak of about 2,600 in 1973. By 1990, the school had fewer than 2,000 students, falling to around 1,700 by 1997.