Today, Montessori preschool groups have become quite widespread in Russia. But parents who want to continue their children's education according to the Montessori system are asking a fair question about primary school. This book is intended to show the difference between preschool and school groups, as M. Montessori herself defined it, and also to highlight the potential of this primary school, widespread in the world , and the prospects for its development in our country. Intended for parents and educators, the book will be useful for teachers and students of pedagogical educational institutions.