Humans are driven by an intrinsic motivation to learn, but the developmental origins of curiosity-driven exploration remain unclear. We investigated the computational principles guiding 4-year-old children’s exploration during a touchscreen game (N=102, F=49, M=53). Children guessed the location of characters that were hiding behind a hedge following predictable (yet noisy) patterns. Children could freely switch characters, which allowed us to quantify when they decided to explore something different and what they chose to explore. Bayesian modelling of their responses revealed that children selected activities that were more novel and offered greater learning progress. Moreover, children’s interest in making learning progress correlated with better learning performance. These findings highlight the importance of novelty and learning progress in guiding children’s curiosity-driven exploration.