Sangaku Maths is an open educational resource that offers the whole theory of mathematics from Secondary to early courses in technical degrees. An own theory, created by an interdisciplinary team, which stands for very didactic explanations, examples and solved problems. In addition, Sangaku Maths has an App so you can have it all also on your mobile or tablet. We offer all this at no cost to you, thanks to a group of entities and individuals who have decided to bet on a new model of education, based on universality, cooperation, and renewal. But what is its purpose? Sangaku Maths is a service from Sangaku, an educational proposal that provides methodologies, technologies, and resources to drive transformation within and outside the classroom, understanding that the educational community, families, and social agents are part of the same ecosystem.