Many countries, American jurisdictions and charter schools have recently embraced longer school days or more time devoted to core academic classes. Recent research generally supports the notion that additional time raises achievement, though difficulties isolating an exogenous source of...

This paper investigates the effects of California's class size reduction program on teacher quality and student achievement in an effort to gain a comprehensive understanding of the impact of a large-scale decrease in class size. It uses year-to-year differences in class size generated by...

Considerable controversy surrounds the impact of schools and teachers on the achievement of students. This paper disentangles the separate factors influencing achievement with special attention given to the role of teacher differences and other aspects of schools. Unique matched panel data from...