Abstract
In the thesis, the characteristic of developmental turning point at the age of 9 or 10 is analyzed from the viewpoint of the development of interests at puberty. According to Vygotsky, there are three phases in the development of interests at puberty, that is, the preparatory, negative and affirmative phases. The developmental turning point at the age of 9 or 10 corresponds to the preparatory phase of the development of interests. The preparatory phase of the development of interests is provided for by a latent, sexual maturation occurring in the depths. It is characterized by absence of any particularly clear dominant intentions or especially keen interests, that is, by a certain lack of general stimulation. It contains the elements of both the negative phase and the affirmative one in an embryonal, undeveloped and unseparated form. Therefore, from the viewpoint of the development of interests, the developmental turning point at the age of 9 or 10 is a prologue for which a real, complete change occurring in puberty is prepared.