Persistence is essential for learning, but children cannot and should not persist at everything. How do young children decide what is worth their effort? We build a theory of young children’s state persistence as the outcome of a socially guided decision-making process between children and caregivers. Integrating research from metacognition, decision-making, and social learning, we show how caregivers shape two key beliefs that guide children’s effort: What children think they are capable of and whether their effort is worthwhile. Caregivers’ actions, in turn, are guided by their own beliefs about children’s abilities and the value of tasks, creating a dynamic social system of effort calibration. By reframing persistence as a dynamic coconstructed process, we uncover how motivation is built—and where it can break down.