UC Davis

Education policies could profoundly impact students’ experience and achievement in school, as well as their long-term human capital accumulation and labor market returns. This dissertation focuses on school-entry policy reforms in China and South Korea and their impacts on students’ school-entry decisions, educational attainment, and mental health. Thefirst two chapters examine a school-starting age reform in China implemented in the 1980s and 1990s. This reform lowered the age requirement for primary school entry from age seven to age six while maintaining the birth date cutoff for enrolling in the current academic year and left the required duration of schooling unchanged. The third chapter focuses on a 2009 South Korean reform that moved the birth date cutoff for enrolling in the current academic year from March 1 to January 1. The first chapter of my dissertation documents the change in the distribution of students’ school-starting age in response to the reform. Utilizing data from the 1982 and 1990 censuses, China Family Panel Studies 2010, and China Health and Nutrition Surveys from 1989 and 1993 for estimation, I estimate the distribution of school starting age before and after the reform using three distinct proxies and document the changes in the distribution. I highlight the similarities and discrepancies of the observed shape and changes in distribution between each proxy and discuss the limitations and contributions of each approach. My findings indicate that the reform substantially increased the fraction of children who started school at age six and reduced the fraction of those who started school after age seven. These changes in school-starting age distribution are robust to the choice of data or proxy and are unlikely to be driven by trends in early enrollments. The second chapter of my dissertation estimates the causal effects of the reform on educational attainment by exploiting the staggered adoption across provinces. Using Chinese 2005 census microdata and implementing heterogeneity-robust difference-in-differences by Callaway and Sant’Anna (2021), I find that the reform increased high school enrollment by 5.5 percentage points and high school graduation by 5.3 percentage points. Heterogeneity analyses reveal more pronounced effects for students with better pre-primary education resources but little difference by gender. Additional analysis suggests that the dynamic complementarity of early skills could be a potential mechanism that explains why starting primary school at six instead of seven enhances long-term human capital accumulation. The third chapter, co-authored with Estelle Shin, examines the impact of changing the school-entry birth date cutoff on students’ mental health, including self-esteem and emotional/behavioral problems such as inattention, aggression, social withdrawal, physical symptoms, and depression. We utilize a difference-in-difference design and detailed mental health survey data from the Korea Children and Youth Panel Survey 2010 and 2018. Our analyses suggest that after the reform, both male and female students born in January and February showed substantially improved early-adolescent mental health relative to peers compared to students born in January and February before the reform. The female students exhibit lower levels of inattention and aggression, while the male students show high levels of self-esteem. Our findings add novel evidence to the growing economics literature on children and adolescent mental health.