Colegio La Paz in Tijuana, Mexico. The Catholic pre- and secondary school started in 1943, when Tijuana's population was a mere 50,000 (now it's two million). Construction began in 1953 and it opened in 1959. The campus is located in the Hipódromo neighborhood, adjacent to Chapultepec.
The school in 1964.
You might remember it from my post on Harry Crosby's trip to Tijuana.
The school seems to be in amazing condition.
Another building on campus.