Chalfant, John C(lay) (b. November 17, 1928, Oregon, USA), educator and director. From 1988 to 1992, he served as the first director of the Koç High School (see Koç School).
Chalfant completed his undergraduate education in literature and social sciences at Fresno State College in California between 1949 and 1952 and received an MA in American Civilizations from Pennsylvania University in 1956. He began his professional career in 1955 as a teacher of English and physical education at Robert College. From 1956 to 1965, he taught physical education, history and English and performed administrative duties at a number of middle schools in the USA and Greece. Returning to Istanbul in 1965, he began working once again at Robert College, becoming its headmaster in 1971. Following his six-year tenure, he served as principal of The Sultan’s School in Oman (1977-86). Chalfant served as project director for the foundation of the Koç High School (1987-88). In 1988, he became the school’s first director, remaining in post until the high school produced its first graduates in 1992. In the 1992-93 academic year, he served as principal of Üsküdar American High School.