"If I'm sending my daughter to an international school, I want a calm environment where she can truly develop her academic potential."
For parents who feel this way, all-girls international schools in Tokyo are a very attractive option. Among them, Seisen International School, located in the quiet residential area of Setagaya, is known for successfully combining a warm, at-home atmosphere with world-class university placements.
However, as you begin your research, you'll inevitably encounter the question: "Which is better, Seisen or the International School of the Sacred Heart (ISSH)?" While both are historic Catholic girls' schools, their educational philosophies are surprisingly different.
In this article, we'll take a deep dive into the features and reputation of Seisen International School, comparing it with its rival, ISSH. We've also included the latest 2025 IB scores and admissions information to help you with your school selection process.
1. In-Depth Comparison: Seisen vs. ISSH — What Are the Key Differences?
First, let's break down the crucial differences between these two schools that many parents consider. The biggest distinction lies in their curriculum (IB vs. AP).
Comparison Point | Seisen | ISSH |
Location | Yoga, Setagaya | Hiroo, Shibuya |
Curriculum | Full IB School (PYP/MYP/DP) | American-style + AP Program |
Educational Features | Japan's first all-girls IB Continuum school. | Based on a traditional American curriculum, with 22 AP (college-level) courses available in high school. |
University Placement Trends | Globally diverse. | Strong North American focus. |
School Culture & Atmosphere | Warm and at-home. | Traditional and cosmopolitan. |
【Key Takeaways for Choosing】
- Who is Seisen a good fit for? Students who are naturally inquisitive and enjoy deep-diving into a single topic. Families considering universities in Europe, Canada, or Japan.
- Who is ISSH a good fit for? Students who want the flexibility to study a wide range of subjects. Families primarily targeting universities in the United States.
A Deep Dive into the World's Top 3 Curricula | IB, A-Level, AP: Which One is Right for You?
2. Latest Academic Results and IB Scores
When you hear "at-home atmosphere," you might wonder if the academics are less rigorous. However, Seisen's academic performance is among the best of all international schools in Japan.
Exceptional IB Diploma Pass Rate
The results of the graduating class of 2025 demonstrate the high level of education.
- Average Score: 35 points (World average: 30.5 points)
- Pass Rate: 97.7% (World average: approx. 80%)
The IB Diploma is notoriously difficult to obtain, yet at Seisen, nearly all students earn the full diploma and achieve scores well above the global average. The school consistently produces high-scorers with 40+ points (out of 45) each year, indicating an extremely high quality of instruction.
Placements at Top Universities Worldwide
Leveraging these high IB scores, graduates go on to attend prestigious universities across the globe.
- International: Harvard, Princeton, Columbia, Stanford, MIT, Oxford, Cambridge, and more.
- Domestic (Japan): Waseda, Keio, Sophia (with Catholic school recommendations), ICU, and more.
Particularly noteworthy is the school's strength in STEM fields. Despite being an all-girls school, many graduates go on to study medicine and engineering, developing their talents in science and math in an environment free from gender bias.
3. The Reality and Reputation of a Catholic Girls' School
We'll address common questions from parents, such as "Is the religious influence strong?" and "Aren't social dynamics difficult at an all-girls school?"
Is it okay for non-Christians?
In short, it's not a problem at all. Many of the students are not Christian. While there are daily prayers and Religious Knowledge classes, these are not intended to force belief but are positioned as part of a character education program to foster a sense of gratitude and ethics. Many parents comment positively, saying, "Through religious events, my daughter has developed a spirit of compassion and service."
The Unique Leadership Opportunities of an All-Girls School
At Seisen, the student council president, sports team captains, and science competition leaders are all girls. By spending their formative years in an environment free from unconscious biases like "boys are better at STEM" or "leaders are men," students naturally develop the confidence that "women can be anything." In fact, it is Seisen's female students who excel in global robotics competitions and science fairs (such as the Firebird team).
4. Admissions and English Language Support
What kind of preparation is necessary for those wishing to enroll at Seisen?
Admissions for Kindergarten (Montessori) to Early Elementary
Admissions for this age group focus more on observational assessments and interviews rather than written tests.
- Playdate Format: During a play-based session with teachers, children are observed on their ability to follow instructions, share toys, and engage with activities curiously.
- English Proficiency: For Kindergarten (K1-K3), native-level English is not required. If a child can say "Hello" and respond to simple instructions from a teacher, they have a good chance of being accepted.
Admissions for Upper Elementary to High School
As students get older, the required level of English proficiency increases significantly.
- MAP Test: Applicants will take the MAP (Measures of Academic Progress) test, an aptitude test in English and Math used by many international schools.
- Essay & Interview: The ability to write logically and articulate one's motivations during an interview is assessed.
- EAL (English as an Additional Language): While English support classes are available, spots are very limited. For transfers into upper grades, sufficient English proficiency to keep up with mainstream classes is generally a prerequisite.
MAP Test (MAP Growth) Score Benchmarks and Prep Strategies: How to Interpret RIT & Percentile Scores and Overcome Plateaus
Conclusion: A School Where Warmth and Intellect Coexist
Seisen International School is a place where the "warm, character-focused education" typical of a Catholic school masterfully blends with the "rigorous inquiry-based learning" of an IB World School. While it might sometimes be perceived as a flashy "finishing school for girls," it is, in reality, more like a "dojo"—a training ground where students from diverse backgrounds challenge each other and grow into independent young women.
If you hope for your daughter to possess both kindness and intellect, and want her to take on challenges in STEM and leadership, Seisen is undoubtedly one of the best environments you can choose.
Aiming for Admission to Seisen International School? Consider "ELT"
At ELT, our native-speaking instructors, who are well-versed in Seisen's admission trends (including Montessori-style observational assessments and MAP test preparation), will support your child's journey to acceptance. We offer comprehensive consulting, from parent interview practice to application essay guidance. Why not start with a free counseling session to assess your child's current English level and chances of admission?
