Seisen International School

Seisen International School is a Catholic, co-educational Kindergarten through Grade 12 international school located in Setagaya, Tokyo. Founded in 1962 by the Handmaids of the Sacred Heart of Jesus, Seisen has been an International Baccalaureate (IB) World School since 1986 — one of the earliest IB schools in Japan. The school offers a co-educational Montessori kindergarten, and an all-girls program from Grade 1 through Grade 12, with boys welcome in the co-ed kindergarten. Seisen delivers the IB Primary Years Programme (PYP), Middle Years Programme (MYP), and Diploma Programme (DP), preparing students for universities worldwide. The school is accredited by the Western Association of Schools and Colleges (WASC) and the Council of International Schools (CIS). Seisen's multicultural student body represents over 40 nationalities, fostering a vibrant global community rooted in Catholic values and a commitment to academic excellence, social responsibility, and personal growth.