Education in Poland tries to keep up with the extremely dynamic civilisation changes in order to prepare students to face the challenges of the future. However, it must face the historical burden symbolically defined as "homo sovieticus"--a man giving up his own agency to the system and authority. The aim of the article is to evaluate the effectiveness of the implementation of the assumptions of self-determination theory (SDT) in developing the emotional-social competences of students (described using the original TROS-KA model) and gaining school achievements. The study was conducted among 10-11-year-old students (n=94), parents (n=94) and teachers (n=28). It confirmed that the annual teaching cycle based on SDT assumptions was more effective (compared to standard practices) both in terms of developing a sense of competence (measured using the TROS-KA scales) as well as school achievements (measured by school grades). Moreover, teachers and parents noticed an increase in the emotional-social competences of the students, their greater involvement in the learning process and an increase in their independence. SDT can be a key strategy in the process of increasing the autonomy of the Polish school and, consequently, in the process of reducing the presence of "homo sovieticus" features in the mentality of Polish teachers.