Within the framework of preparations for the project of the further development of the Czechoslovak educational system a new conception of the first stage of the elementary school has been elaborated. This conception follows up the programme of uniform educational work in crèches and nursery schools, and its orientation is in keeping with the age characteristics of children of junior school age as well as with the characteristic features of educational organisation at this stage of schooling. The original hypothetical project of the first four-year stage of the elementary school was based on a general theoretical conception of the initial stage of education in the framework of the socialist educational system. It was verified in the course of long-term experimental work of many researchers at selected elementary schools, and after the successful verification it is being gradually put into practice starting from the first year of the elementary school. The elaboration of the theoretical conception of the research as well as the research itself can be considered as an important step forward from the speculatively descriptive character of solving pedagogical problems in this area to a theoretical empirical way of solving them. This scientific approach to the solution of the above-mentioned problems opens up a possibility for educationists to build up a theoretical system of pedagogy for the first stage o-f the elementary school, based on a system of knowledge of the psychology of the pupil of junior school age and the knowledge of the specific characteristics of the pupil’s learning activity, and reflecting the specific laws governing the educational process at the first stage of the elementary school. The elaboration of this system will make it possible for the prospective improvement of the educational process at this stage of schooling to be based on a scientific theoretical conception.