AI Matters
Why it matters
Large-scale study links AI homework help to lower exam scores
The Decoder A 26,000-student study shows AI's hidden learning cost takes two full years to surface
A study of over 26,000 students in China found that those using AI tools scored up to 24 percent lower on exams, despite completing homework faster. Researchers noted that the negative impact on learning took up to two years to fully surface.
Why it matters
While AI helps students finish homework faster, it can lead to a significant drop in actual exam performance over time.
Latest brief · Jul 22, 2026