Open Access

In response to the globally increasing environmental, social, and economic crises, we as humanity must leave the path of business as usual and learn new ways to know, think, and act which may enable us to build a more sustainable future for all. In their role as facilitators, teachers in general are considered one, if not the most important, factor for successful learning. The implementation of education for sustainable development (ESD) across all education systems and preparing students to act as future change agents and lead the societal transformation towards sustainability also largely depends on competent and committed teachers. Correspondingly, the focus of political agendas and scientific research increasingly shifts to the effective education of educators. The different competence models that are currently being discussed in the international discourse around teacher education for sustainable development (TESD) suggest various sets of intended learning outcomes (ILOs). Yet, they usually share the assumption that teachers require ESD-related knowledge, pedagogical skills, and motivation to successfully implement ESD at the school level. In accordance with the concept of ESD-specific professional action competence (Bertschy et al., 2013), educational offers in ESD for pre-service teachers should also develop their content knowledge (CK), pedagogical content knowledge (PCK) as well as a positive attitude towards ESD. However, in the sense of a comprehensive construct, this concept has not yet been operationalized or measured. Furthermore, there is still a lack of deeper understanding as to how to best design individual courses as teaching and learning environments in TESD in order to support competence development in student teachers. Based on a dual case study, this cumulative dissertation investigates how individual ESD courses, as part of the teacher education programs at Leuphana University in Lüneburg/ Germany and Arizona State University (ASU) in Tempe/USA, actually foster students’ ESD-specific professional action competence. Furthermore, this work sheds light on the link between learning processes and outcomes, to reveal which factors actually affect the achievement of ILOs and competence development. The findings of this study indicate that both courses under investigation eventually live up to their role and increased student teachers’ competence and commitment to implement ESD in their future careers; yet, mainly due to their different thematic foci, to varying degrees. Additionally, the four Cs (personal, professional, social, and structural connections) were revealed as significant factors that support students’ learning and should be considered when planning and designing course offerings in TESD, with the goal of developing students’ knowledge, skills, and attitudes.