Class Size
The first reaction to weak educational achievement is often to demand smaller class sizes. An extensive research literature shows, however, that smaller classes do not generally lead to better student achievement. In international comparison, countries with smaller classes do not show systematically better achievement of their students. Similarly, within countries students taught in smaller classes do not generally learn more. At the same time, class-size reductions are very expensive. If the aim is really to increase the learning outcomes of students, class sizes and spending levels cannot be the main focus. Instead, the focus has to be on other reforms, such as external exams, school autonomy, and competition.
Two-pager:
Class Size: Does It Matter? (with E.A. Hanushek). EENEE Policy Brief 2/2011
Non-technical overviews:
International Evidence on Expenditures and Class Size: A Review. Brookings Papers on Education Policy 2006/2007: 245-272, 2007
Crowd Control: An International Look at the Relationship between Class Size and Student Achievement (with M.R. West). Education Next 3 (3): 56-62, 2003
Here you can learn more about my research on this topic.
My most important academic papers on the topic are:
Class-Size Effects in School Systems around the World: Evidence from Between-Grade Variation in TIMSS (with M.R. West). European Economic Review 50 (3): 695-736, 2006
Educational Production in Europe. Economic Policy 20 (43): 445-504, 2005