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Columbia International School is a K–12 school in Tokorozawa, west of Greater Tokyo, with access via Higashi-Tokorozawa Station on the JR Musashino Line. Teaching follows the Ontario (Canada) curriculum and all courses are taught in English, with Japanese (Kokugo) lessons offered daily up to Grade 8. The school offers a boarding program, with a dormitory located about an 8-minute walk from campus and supervised daily by a resident dorm supervisor. Co-curricular options listed by the school include activities such as art, newspaper, soccer, music club, yearbook club, photo club and drama club. For older students, the school notes that the Grade 11 Guidance Overseas Trip (G.O.T.) is a compulsory activity.