This article explores the relation between curiosity and interest by examining how in-the-moment experiences of curiosity and of interest emerge out of exploratory behavior observed in infancy and early childhood. As experiential states, there is little to distinguish curiosity and interest. Descriptions of developing interests that refer to "curiosity questions" and "curiosity episodes," suggest that experiential states of curiosity and interest are intertwined in interest development. However, when the focus is on individual differences, curiosity and interest diverge. Trait curiosity is a relatively stable personality trait, the propensity to feel curious in contexts high in collative variability. On the other hand, interests or individual interest refer to a disposition or predisposition to engage and re-engage with contents of a specific domain. It is suggested that further insight into the significance of curiosity and interest for educational practice will come from expanding real-time analyses of the quality of the experiential states they subsume.