This paper discusses self-efficacy as a key factor in children managing the transition to primary school, the threshold to formal education and further learning processes. In presenting results of a qualitative-longitudinal interview study of German preschool and primary school children's perspectives on their self-efficacy experiences, it furnishes evidence for enhancing self-efficacy in pedagogical practice in a so-called mastery climate. Co-determined or self-determined opportunities for playing without adult intervention prove to be central in this to children's self-efficacy. Following on from this, the discussion will make references to the pedagogical relevance of child-led or unsupervised play for the promotion of self-efficacy in both settings. In addition, based on the reflection of the concept of generational order, the study points to concrete starting points to focus on necessary didactic and methodological competences of adult educators for the appropriate design of child-oriented co-determined or self-determined learning settings.