The impact of China's “Double Reduction” policy on primary school students' subjective well-being and academic achievement

China's "Double Reduction" policy, launched in 2021, seeks to reduce academic pressure on students in compulsory schooling. Using a two-wave logitudinal survey data (Sep 2021 to Jun 2023) from 1402 fourth- to fifth-grade students in a Beijing district and applying a first-difference approach with Lasso control for causal estimation, this study examines how three key policy initiatives —reducing homework, regulating private training institutions, and requiring schools to provide after-school services—impact students' subjective well-being and academic achievement. Our estimations find that reducing homework time and providing school-based after-school services improve students’ subjective well-being without compromising their academic performance. In contrast, while regulating private tutoring institutions increases subjective well-being, it decreases academic achievement among low-SES students. This research highlights the complex, and potentially inequitable consequences arising from the "Double Reduction" policy, emphasizing the critical trade-off for future policy adjustments.