In the learning journey of young children, rewards are ubiquitous. Yet, psychologists and behavioral economists question the success of rewards and even claim that they displace intrinsic motivation, a phenomenon referred to as motivation crowding out. While information systems can help children learn everyday tasks, it is unclear if and when digital rewards produce motivation crowding out. Theoretically sound, empirical field studies on this topic are lacking and existing information system research on motivation crowding is limited to specific domains, not covering children’s behavior. Therefore, we aim to elicit how digital rewards influence an everyday health behavior that children learn in kindergarten – handwashing – and the underlying intrinsic motivation. We conduct a randomized controlled trial that is conceptualized in this paper. Our results will extend motivation crowding theory in the context of young children and inform the design of digital behavior change interventions.