Humans have a long childhood in comparison to all other species. Across disciplines, researchers agree that humans’ prolonged immaturity is integral to our unique intelligence. The studies presented here support the hypothesis that human beings’ extended childhood pays off in the form of an ability to learn more about changing environments. Across two studies (n = 213), children and adults played a game where they chose among four different cartoon monsters yielding different numbers of star rewards. Adults focused on maximizing reward, while children chose to explore longer, even at the cost of earning fewer stars. As a result, adults won significantly more stars than children did. However, in the ‘dynamic’ version of the task, the rewards given out by the monsters changed halfway through: the monster that had been giving out the fewest stars began giving out the most. Because children continued to explore whereas adults ignored the low-reward monster, children were much more likely than adults to detect the change. This illustrates that while exploration may be costly in the short term, it leads to a more flexible understanding of the world in the long term, particularly when that world is changing.