What Ranius builds is not courseware and not an app. It is the process that makes a teacher. Japan or the US — either is fine.
What you can do
The Ranius community is for people who want to build, with us, the way teachers are developed. Membership is by approval. Once in, you can do these four things. The screens are from Teacher Studio, which we are building now.
01 Researchers & measurement
See lessons whose teachers agreed to share them, together with the AI's time-stamped evidence for each criterion. How far does the AI agree with human raters, and on which criteria does it drift? Find out on real classrooms, not hypothetical cases.
02 Researchers & teachers
The hardest problem in this system is legitimacy. We will not decide on our own what a teacher is judged on. Comment on the draft criteria and help us examine how much raters disagree.
03 Engineers & AI founders
Teacher Studio has a space called "Let's build apps together". Teachers post what they need; someone builds it. Your AI or app goes in front of the teachers who will use it.
04 Every member
NIJIN Academy, run by our parent company, has about 500 children and about 100 instructors. You do not have to start by finding a place to test. That is the biggest difference from other communities.
The screens are in development and the content shown is illustrative. Which lessons and data members can work with will follow teacher and parent consent and research-ethics review. The figures of about 500 and about 100 belong to NIJIN Academy, run by NIJIN Inc.; 500 is enrolment, not the number of research participants.
Team Ranius
These three people run Ranius today. The expertise we are missing is clear.
Founder
Tatsuro Hoshino
A former public elementary school teacher who founded NIJIN Inc. in 2022. He built NIJIN Academy, an online school for children who cannot attend school, and a learning community for teachers. At Ranius he sets the direction of the business and the research.
Classroom & teacher development
Takashi Isa
Leads instructor hiring and development at NIJIN Academy. At Ranius he runs the teacher-development process in real classrooms and checks whether the certification bar holds up in front of children.
Pro bono / Business development
Masaaki Itakura
After working on strategy, operational reform and digital transformation at global consulting firms, he became an executive at an insurance company in Brazil, overseeing eleven departments including HR, corporate planning and marketing, and chairing its AI committee. A long-time supporter of job training for young people from low-income families, he founded a non-profit for the next generation in 2026 and serves as its chair. BA, UC Berkeley; MBA, Bocconi University. Speaks six languages.
Your seat
Open
Research lead, measurement, engineering, business development. If you are close to any of the four seats below, let us talk for 30 minutes. If none fits but there is something you want to try in Ranius, you are welcome too.
All four are seats we want filled now. Open a heading to see what the work is. Japan or the US — either is fine.
Turning "watch a lesson, return evidence" from human hours into software. This is the bottleneck.
Whether we can say "equivalent" out loud depends entirely on how this person designs it.
A single lesson observation has reliability 0.14–0.37. Until that number moves, none of our claims are proved.
As the payer moves from L1 to L2 to L3, the child's cost approaches zero. We are looking for the person who builds that order.
Three ways to be involved: pro bono (2–5 hours a week), contract / side work (6–10 hours a week), or full time. You can change the form later.
Masaaki Itakura takes part in a personal capacity, not on behalf of his employer.
CONTACT
No CV needed. Pick the role and the shape of the arrangement, and send it. Pro bono — a few hours a week — is welcome. Tatsuro will come back to you within a few days.
We use what you send only to contact you about this, and never pass it to third parties. If it does not fit, say so on the call.