The Causal Effect of Active School Travel on Children’s Subjective Well-Being: Evidence from the China Family Panel Survey

School travel, as an integral part of children’s daily life, has important implications for their subjective well-being. However, previous studies more focused on the effects of school travel on physical health, and few of them paid attention to the subjective well-being of children. The cultural backgrounds differ between domestic and foreign contexts, rendering foreign research not necessarily applicable to China. This study aimed to explore the functional mechanism and causal effect of active school travel on children’s subjective well-being. We used 4 waves of data from the 2012–2018 Chinese Family Panel Studies (CFPS) and employed the random-effects ordered logistic model as well as the Double Machine Learning (DML) model to investigate the causality between active school travel and children’s subjective well-being. Our study revealed a significant positive effect of active school travel on children’s subjective well-being. The research findings validated that DML is an appropriate and beneficial method for studying the causal relationship between children’s subjective well-being and active school travel. Moreover, these results provide valuable insights for policymakers and practitioners to develop child-friendly travel policies and infrastructure.