Mathematical competencies develop from birth, and children in daycare centers already possess considerable mathematical skills, which can vary significantly among the children. In recent years, various support programs have been increasingly developed. Two fundamental conceptual approaches can be distinguished: training programs and everyday integrated support, the effectiveness of which was comparatively examined in the present study. As part of an intervention study, educators were trained in the implementation of structured mathematical training or everyday integrated mathematical support. This aimed to answer the question of how the effects of professional development and concurrently provided support on children's skill development differ depending on the support concept.