A 26,000-student study finds AI's learning cost takes two years to surface

The unsettling part of this study is not that AI helped with homework, it is that the damage from over-relying on it was invisible for months and only showed up once students had to perform without a tool in the room. Schools rushing to adopt AI tutors on the strength of short-term score bumps are flying blind on exactly the timescale that matters most. This is a case where the good headline number and the true cost live years apart, and anyone designing ed-tech policy should be asking for longitudinal data, not semester snapshots.