Seisen International School (SIS) is an all-girls,
Catholic school located in
Setagaya-ku, in
Tokyo,
Japan. Students and faculty from over sixty countries are represented at Seisen, with
English being the main language of instruction. It offers the
International Baccalaureate program for grades 11 and 12. It is accredited by the
Ministry of Education, Culture, Sports, Science and Technology (Japan),
New England Association of Schools and Colleges and the
European Council of International Schools. It teaches
Montessori kindergarten (coed, ages 3–6) and grades 1-12 (girls only, ages 6–18).