The aim of this study was to investigate self-theories (theories of intelligence, confidence in one's intelligence, internal attribution of failure, academic self-efficacy), specific control, and experiencing of stress by means of a questionnaire for 915 Swedish high school students. Factor analysis yielded 6 stress domains (Workload, Psychosocial Problems, Uncertainty, Problems in Close Relationships, Demands to be Met, Problems of the Physical Environment). The balance between control and stress was measured by the Control-Stress Index. Most of the adolescents' stress appeared to be connected with their schoolwork. Female students, especially in academic programs, experienced greater stress and greater deficit of control than male students. Sequential regression analyses showed that final grades could be predicted to 28% from demographic variables, self-theories, and stress. The contribution of stress was 4%. (Contains 7 tables and 2 notes.)