This book contains the scientific aspects required by the teacher of the primary education on the introduction of natural numbers, rational numbers, concepts of geometry, sizes and measurement units as well as the methodological aspects necessary for the transmission of specific concepts in the field of mathematics. We thus try to train their children concentration, listening, communicating, to gain enough experience, so that they can form the necessary basis for understanding mathematical concepts and systems and to be able to say that we have passed the first level. In the long journey alongside mathematics, during primary school, children will be guided to form the basis for understanding mathematical concepts and systems. The objective of the teacher is to provide each student with the essential mathematical knowledge and skills, so as to train their children the skills necessary for the conduct of the activity both in everyday life and in later professional life, which is increasingly based on mathematics logic and technology.