By the 1940s, the student body had grown to more than 900 primarily Western children; the present building was built in 1949 with funds provided by ARAMCO.

The American High School Diploma program prepares students for admission to colleges and universities in the US.

[citation needed] The ACS campus is located within a short distance from the Mediterranean sea.

The Lower School building consists of a library, computer center, auditorium, multipurpose hall, art room, as well as the Early Childhood and the Elementary Administrative Wing.

[citation needed] The athletics program partakes in several sporting conferences, including NESAC along with locally held tournaments.

The Junior Knight Award is presented to one male and one female from grades 9 and 10 who demonstrate outstanding dedication, skill, sportsmanship, and leadership.

The Farah Family Athletics and Leadership Award is presented to the senior who excels in the academic program at ACS Beirut, demonstrates leadership and commitment, and positively impacts the athletic and academic life at ACS Beirut.