We are approaching the end of our study. We began with a review of the changes that occur in the structure of the organism and its most important functions during the period of sexual maturation. We were able to trace the complete restructuring of the whole internal and external system of activity of the organism, the radical change in its structure and the new structure of organic activity that is connected with sexual maturation. Tracing many stages, passing from drives to interests, from interests to mental functions, and from these to the content of thinking and to creative imagination, we have seen how the new structure of the adolescent's personality, which differs from the structure of the child's personality, is formed.