Class size reduction helps raise student achievement

The evidence that class size reduction helps raise student achievement is strong according to
Professor Diane Whitmore Schanzenbach’s report, Does Class Size Matter?, published today by the National Education Policy Center (NEPC) at the University of Colorado Boulder. The report provides a comprehensive review of class-size research.

According to Professor Schanzenbach, class-size reduction has been the victim of a popular misconception that the strategy has been largely unsuccessful. One recent example, Schanzenbach notes, is the writer Malcolm Gladwell, who in a recent book describes small class sizes as a “thing we are convinced is such a big advantage [but] might not be such an advantage at all.”

In fact, she writes, the real story is just the opposite. “Class size matters,” writes Schanzenbach, an economist and education policy professor at Northwestern University in Evanston, Illinois. “Research supports the common-sense notion that children learn more and teachers are more effective in smaller classes.”

Citing evidence from the academic literature, Schanzenbach explains that “class size is an important determinant of a variety of student outcomes ranging from test scores to broader life outcomes. Smaller classes are particularly effective at raising achievement levels of low-income and minority children.”

Conversely, she points out, raising class size can be shown to be harmful to children. “Money saved today by increasing class sizes will result in more substantial social and educational costs in the future,” she writes.

“Policymakers should carefully weigh the efficacy of class-size policy against other potential uses of funds,” Schanzenbach concludes. “While lower class size has a demonstrable cost, it may prove the more cost-effective policy overall.”