The article finds out the influence of positive psychological interventions (PPI) on adolescents’ well-being (N = 13). Author explores the foreign experience of fulfillment of strength-based interventions in schools and various changes in well-being of school students as the result of such fulfillment. The course of interventions is made by the author based on the Strengths Gym program. The main features of the course are: the group exercises which aim to apply the use of strength, and the format of session, which is 45 min. each of 4-ssession course. Moreover, some of well-being self-reports are adopted for the Russian-speaking adolescents for the first time. The results show that the PPI have a significant positive influence on positivity ratio of emotions, which is the main target of any similar interventions made within positive psychology. The fulfillment of strength-based intervention is made for the first time in the Russian scientific research and the results are consisted with foreign experiments. The article shows a utility of such short-course PPI in schools in order to enhance adolescents’ well-being. One of the possible goals of a future research is to find out factors of such positive changes of adolescents’ well-being.