This paper exploits quasi-experimental variation in the return to education created by the shock of China's accession to the World Trade Organization (WTO) to evaluate its impact on a critical component of human capital accumulation—high school enrollment. Since this shock varies over both time and space, I construct measures of prefecture trade exposure using data on the initial industrial composition, variation in industrial tariff reductions, and spatially determined geographic trade costs, and then evaluate both the short- and long-run impact of the shock. By using detailed administrative data on youth aged 16 from 1995 to 2014, I find a one standard deviation increase in exposure caused an 8% relative decline in high school attendance for the earliest affected cohort. Surprisingly, this drop in enrollment persists and even grows over time. This suggests that China's accession created an export-driven demand shock biased toward less-skilled workers, which was, in turn, magnified by subsequent complementary investments.