JOH, Mary Kim

Mary Kim Joh (1904–2005), also known as Che Sik Cho, was a Korean-American composer, academic, and medical research scientist. After studying at Ewha Womans University and earning a master's degree in music from the University of Michigan, she taught in Ewha's music department. Following the end of Japanese rule in 1945, the South Korean government commissioned her to compose children's songs to help replenish Korean-language educational materials. Among these, she wrote the iconic nursery rhyme "School Bell" (Hak'kyo Jong), which remains widely taught to young students across South Korea.

In addition to compiling a foundational 1950 publication on Korean folk melodies, Joh later transitioned into a second career in medical science after moving to the United States. Holding a master's degree in science from Wayne State University, she worked in hospital laboratories and served as a Peace Corps volunteer in Liberia at age 73.