Systems thinking is regarded as a key competence in the field of education for sustainable development (ESD), because it helps students to understand the complexity and dynamics of natural, social and economic systems. In our research group, we developed a competence model that distinguishes four dimensions of systems thinking in ESD. Based on this model, we designed different university courses in biology and geography teacher education and measured their effects on student teachers' systems thinking and the pedagogical content knowledge for teaching systems thinking with two different tests. Both variables could be effectively promoted depending on the course.