RT Journal Article SR Electronic T1 Long-Term Impacts of Class Size in Compulsory School JF Journal of Human Resources JO J Hum Resour FD University of Wisconsin Press SP 309 OP 348 DO 10.3368/jhr.55.2.0217.8574R2 VO 55 IS 1 A1 Leuven, Edwin A1 Løkken, Sturla A. YR 2020 UL http://jhr.uwpress.org/content/55/1/309.abstract AB How does class size in compulsory school affect people’s long-run education and earnings? We use maximum-class-size rules and Norwegian administrative registries, allowing us to observe outcomes up to age 48. We do not find any indication of beneficial effects of class-size reduction in compulsory school. For a one-person reduction in class size we reject effects on income as small as 0.12 percent in primary school and 0.15 percent in middle school. Population differences in parental background, school size, or competitive pressure do not appear to reconcile our findings with previous studies.