We investigate the effects of a large-scale Norwegian reform that provided extra teachers to 166 lower secondary schools with relatively high student-teacher ratios and low average grades. We exploit these two margins using a regression discontinuity setup and find that the reform reduced the...

Several recent studies find that interventions in schools can have important lasting consequences for students, and that schools differ in their contribution to students' learning. However, there is less research investigating how these differences between schools influence longer-term outcomes,...