A study of more than 26,000 Chinese students shows that using generative AI for homework improves short-term results but leads to significantly lower exam scores over time.
Researchers from Stockholm University and the University of Hong Kong tracked middle and high school students in a county in central China from September 2022 to June 2025. They compared AI users with non-users on homework grades, completion times, monthly tests and entrance exams.
AI use raised homework scores by 18 percent and reduced time spent from 64 minutes to 45 minutes. However, monthly exam scores fell by 20 percent within six months. After two years, Zhongkao results dropped 24 percent and Gaokao results dropped 18 percent.
The scholars noted that students may develop a deceptive sense of fluency because AI makes tasks feel effortless. The study was published on the Social Science Research Network.
