The book "Theoretical foundations of the course of mathematics of primary school (elements of combinatorics): a textbook", created by a team of authors, is a unique and in-depth study of the fundamental aspects of teaching mathematics to the youngest students . This is not just a textbook - it is the key to understanding how the first ideas about mathematics are formed in children, and how to properly build the educational process so that it is not only cognitive, but also inspiring. The focus of this book is on the elements of combinatorics, one of the most fascinating and at the same time complex areas of mathematics, which helps to develop logical thinking, analytical abilities and ability to solve problems. The authors, who have rich pedagogical and scientific experience, masterfully reveal the theoretical foundations of the elementary school mathematics course, making the material accessible and understandable for teachers, students of pedagogical universities and parents interested in quality education of their children. What makes this manual special? First, it combines theory and practice, offering not only an explanation of the basic concepts of combinatorics, but also specific techniques, exercises and examples that are easy to integrate into the learning process. Secondly, the book raises important topics for the development of mathematical literacy in younger schoolchildren, shows how to make learning interesting and interactive, using game methods, visual materials and didactic techniques. As a result, the book becomes a real guide for those who want not just to teach mathematics, but to inspire children to learn and discover new horizons. Particular attention is paid to how to form a steady interest in mathematics in elementary school students, to develop their analytical abilities and the ability to think logically. The authors analyze in detail the main theoretical provisions related to combinatorics, and show how this knowledge can be applied in solving a variety of problems, from simple exercises to more complex tasks that stimulate creative thinking. Theoretical foundations of the course of mathematics of primary school (elements of combinatorics) : The textbook" will be especially useful for teachers working with junior schoolchildren, students of pedagogical universities, as well as parents seeking to understand how to properly prepare a child for successfully mastering mathematics. It is suitable for readers interested in the development of logical thinking, teaching methods and innovative approaches to teaching mathematics. The author's team, known for its systematic approach and attention to detail, created a work that not only expands theoretical knowledge, but also inspires practical application. In the style of the authors, there is a deep understanding of pedagogical psychology, as well as a passion for the development of mathematical literacy in children. Their other well-known works, devoted to the methods of teaching mathematics and the development of critical thinking, confirm the high level of professionalism and innovative approach to learning. If you are looking for a book that will help you understand how to make mathematics fun and understandable for beginner students, “Theoretical Foundations of the Elementary School Mathematics Course (Combinatorics Elements): A Tutorial” will become an indispensable assistant. This edition will open up new horizons of pedagogical skills and help to form a solid basis for further mathematical development in children. In today's world, where analytical skills and logic play a key role, this book deservedly takes its place in the library of everyone who appreciates quality education and strives for the development of future generations.