Using the facilities of the Unitarian Church on West Front Street in Lincroft, New Jersey, Oak Hill Academy opened its doors in September of 1981 to students in seventh and eighth grades. In 1984, the school, now including a sixth grade, moved to a ten-acre campus on Middletown-Lincroft Road in Lincroft. The facilities included a ten-classroom building, an administration building, and a pool. The following years saw the addition of a fifth grade, as well as a gymnasium, library, and Commons building with expanded lunchroom, computer room, and offices. Outdoor facilities included a baseball field, soccer field, basketball court, and playground. In 1989, another classroom wing was built to accommodate the Lower School. Recent additions have included a technology center, expanded science lab, art room, outdoor tennis courts, Lower School "Heads-on/Hands-On" room, and a permanent indoor pool enclosure.  The new millennium brought VISIONS 2000, a capital campaign that funded a new library, art, drama, and music building. 

In 2001, the school acquired 4+ acres of property adjacent to its fields on West Front Street. The multi-family home located on the property was converted to a state-of-the-art Center For Early Learning. The facility houses pre-kindergarten and kindergarten.

The year 2005 brought a new addition to Oak Hill's campus: a large student activities center. This facility includes a main room with large seating space, an indoor and outdoor stage, kitchen, and dressing rooms. The new building also includes a media room for multimedia production, new computer classroom, and distance learning center.