Purpose: The purpose of this paper is to review two school intervention projects aiming to promote students' self-efficacy in Germany. Self-efficacy, defined as people's "beliefs in their capabilities to organize and execute the courses of action required to produce given attainments", is a core prevention criterion of mental health. It is positively connected to important facets of personality (e.g. motivational orientation, social competencies) as well as to health-related situation-specific behaviour (e.g. coping with stress, conflict solving). Design/methodology/approach: Two intervention projects, "Self-efficacious Schools--SESC" and "Fostering Self-efficacy and Self-Determination in class--FOSS", made teachers familiar with the concept of self-efficacy to enable them to develop and adapt intra-curricular promotion measures of students' school self-efficacy and social self-efficacy. Findings: Individualisation of task demands and performance feedback as well as a high transparency of teachers' demands and evaluation criteria are beneficial for students' school self-efficacy. Social self-efficacy is enhanced by establishing a positive class climate, where students support each other and teachers are sensitive to the individual needs of their students. Research limitations/implications: Both FOSS and SESC are multi-component non-randomised controlled studies. Thus, future research is needed focusing on the different measures separately using RCT-designs. Practical implications: The actual implementation of promoting strategies into school lessons is the decisive step of strengthening students' mental health at school. As a consequence, promotion measures have to be embedded into organizational structures which can motivate teachers to learn and implement innovation even under unfavourable conditions. Originality/value: In contrast to extracurricular activities, there has been limited research on the implementation and evaluation of prevention activities continuously integrated into the mainstream school curriculum and normal lessons. (Contains 4 figures.)