Across thousands of classrooms, a quiet displacement is underway: artificial intelligence is absorbing the struggle that once built young minds. A large-scale study of Chinese secondary students has revealed that AI assistance lifts homework scores while quietly eroding the deeper comprehension those scores are meant to reflect — and neuroscientists warn the consequences may not fully surface until decades later, when the cognitive reserves never built in youth are needed most. The question now before educators is an ancient one in modern dress: how do we ensure that the tool serves the learne