Do differences in schools' instruction time explain international achievement gaps? Evidence from developed and developing countries

The time that children spend in school varies across countries. Do these differences explain international gaps in pupils' academic achievements? In this article I estimate the effects of instructional time on students' achievement using PISA 2006 data, which include data samples from over 50 countries. I find that instructional time has a positive and significant effect on test scores, and that the effect is much lower in developing countries. Evidence also suggests that the productivity of instructional time is higher in countries which implemented school accountability measures or that gave schools autonomy in budgetary decisions and in hiring/firing teachers