Cities / Tokyo / Seisen International School
Seisen International School
Catholic all-girls IB Continuum school (Montessori, PYP, MYP, Diploma) in Yoga, Setagaya, serving around 650 students from 55+ nationalities. Japan's first all-girls school to offer the IB Diploma (1986) and the first all-girls IB Continuum school in Japan (2020). A…
In brief
An all-girls Catholic IB continuum school in Setagaya, with a co-ed Montessori kindergarten feeding into single-sex grades 1 to 12. One of the established names for families set on a girls' school in Tokyo.
Seisen has been running the IB Diploma since 1986 and now offers the full PYP, MYP and DP continuum, the first all-girls IB continuum school in Japan. Around 700 students from over 40 nationalities attend across K to 12. Diploma results sit well above the world average, with a steady pull of 40-plus scores each year. The Yoga campus shares a site and history with the boys' school St. Mary's, and many sibling families split the two.
Families pick Seisen for the combination of academic seriousness and a school that still feels like a community. The sports programme draws particular praise. The Catholic framing shapes ethos rather than day to day teaching, and the school takes students of all faiths. The single-sex format is the deciding factor for most families who arrive here.
Fees
| Fee | Age | Type | Amount |
|---|---|---|---|
| Kindergarten (Full Day) | 3 | Annual | $2,300,000 |
| Elementary (Grades 1 - 5) | 6 | Annual | $2,450,000 |
| Middle School (Grades 6 - 8) | 11 | Annual | $2,470,000 |
| High School (Grades 9 - 12) | 14 | Annual | $2,470,000 |
| Application Fee | One-time | $20,000 | |
| Registration Fee | One-time | $300,000 | |
| Land & Building Development | One-time | $500,000 |
Reviews
- Discussed often in Tokyo expat threads as one of the city's established Catholic, all-girls international schools, alongside Sacred Heart, with St Mary's as the boys' counterpart in the same Yoga area.
- Parents describe small class sizes, accreditation and a familiar mix of expat and bicultural families, and treat it as a safe choice if a place opens up.
- Teachers and r/teachinginjapan place it in the upper packages tier in Tokyo, generally below ASIJ, BST and YIS but alongside St Mary's, ISSH and TIS.
- Older forum reviews point to the elementary school running with higher teacher turnover than the middle and high school, which sits more stable.
Head of school
Ms. Colette Rogers
Ms. Colette Rogers serves as the Head of School at Seisen International School. She oversees a community that is an International Baccalaureate Continuum school, offering internationally recognized curriculum from Kindergarten to Grade 12. She is committed to providing a curriculum that addresses local and global issues, inspired by the legacy of the Handmaids of the Sacred Heart of Jesus. Under her leadership, the school focuses on empowering students to become communicators, risk-takers, and reflective inquirers, preparing them for success beyond successful exam results.
Accreditations
- Council of International Schools 01
- New England Association of Schools and Colleges 02
Academic results
- IB DP Average 2025 35
- IB DP Pass Rate 2025 97.7%