The article is devoted to the study of the level of critical thinking of adolescents. The article defines the ability to think critically and considers the indicators of the critical thinking ability of adolescents. The features of the development of adolescent thinking and the level of critical thinking are studied. The relevance of the study of this ability is also noted. The basis of critical thinking is formed in childhood and develops and matures in adolescence. The development of critical thinking will allow the teenager to avoid difficult situations and not be afraid to express himself. It is necessary to think critically about the inability to overcome obstacles, the need to overcome the fear of trials and depression in a timely manner and educate students in certain situations the ability to distinguish and understand good and bad in life.   In addition, the article presents the results of the study, depending on the level of development of students ' critical thinking on the basis of the school.