Over the course of the past few years Hyunjoon ParkJere Behrman, and Jaesung Choi have written about the relationship between single-sex schools students' STEM (science, technology, engineering and mathematics) health outcomes. Recently a 2012 Working Paper about this topic was listed on SSRN's Top 10 download list for: Gender in the Global Research Landscape. In a forthcoming version of the article Park, Behrman and Choi discuss the assignment of students into single-sex vs. coeducational high schools in Seoul, South Korea which provides an interesting context to study causal effects of single-sex schools.