Does all work and no play make elite students? Evidence from the China education panel survey

This paper examines the role of after-class learning time in educational performance. In the Program for International Student Assessment (PISA) 2015, Chinese students spent the longest time on study out of school compared with OECD countries but ranked only 10th in mathematics, reading and science. It is doubtful that the longer students study after school, the better their academic performance will be. Based on a representative survey of middle school students in China, we draw on generalized propensity score matching to explore the causal effect between after-class learning time and academic performance, find that the two have a relatively stable "inverted U" relation, and determine that the best academic performance can be achieved when after-class learning time is kept at 3 h per day on weekdays and 8 h per day on weekends. More than these optimal times will hinder academic performance. We further find that the effect of after-class study time on academic performance varies among different groups. There is evidence that after-class learning time influences academic performance through two channels: students' perceived learning difficulty and self-efficacy. This paper concludes that in addition to the appropriate homework assigned by teachers, parents should keep extracurricular tutoring for their children within a reasonable amount of time to maximize students' academic performance.