Yokohama American School got underway in 1946 when the Eighth Army took over a girls’ commercial college. The school started with eighteen students and two teachers. The original building consisted of a three-story structure with twelve classrooms, a gym, auditorium, lab room, sewing room and an art studio. By September 1947, the school had grown to 150 students and ten teachers. In 1948 it produced its first graduating class of 24 students. In 1947 and 1948, two separate elementary schools were opened, Nasugbu Beach and Negishi Heights, respectively. As a result of the Peace Treaty of 1952, the Commercial College was returned to the Japanese and the high school moved to Nasugbu Beach Elementary School. Yokohama American School was originally an Army school and in 1959 the school became a Navy School. The name of the now high school was changed to Nile C. Kinnick High School.
Sports football, baseball and basketball. Played army teams as well as two other high schools.
A Girls’ Athletic Association was organized by 1949 and provided the opportunity for girls to qualify for a sports letter if they participated in five major sports.
Two modern languages, French and Spanish, were taught as well as Latin. There were the typical American curriculum courses in mathematics, science, history, social studies and English. The school sponsored clubs for journalism, drama, chess and checkers, marksmanship and a glee club. The school newspaper, The Yo-Hi Echoes was published twice monthly and the yearbook, Yo-Hi, was published at the end of each year.
The school colors were red and white and the school mascot was the Red Devil.