Class Size Wars

Do small classes boost student performance? Many parents and teachers think so: polling generally reveals widespread support for class size reduction.

Decreasing class size is also popular among legislators, prompting billions of dollars in expenditures to fund ever-shrinking classes in states from California to North Carolina.

But what does the research say? Reams of data have failed to establish a convincing and consistent relationship between smaller classes and high achievement.
Supporters of class size reduction programs point to the STAR (Student Teacher Achievement Ratio) project in Tennessee as evidence that learning improves when class size diminishes. This four-year longitudinal study, comparing classes of 13-17 students with those including 22-25 students in kindergarten through third grade, found that students in smaller classes outperformed their peers in regular classes.

But researchers, including scholar Eric Hanushek, have pointed out flaws in STAR’s project design. In a 1999 Educational Evaluation and Policy Analysis journal article, Mr. Hanushek noted the STAR program’s high rate of student attrition: “Of the initial experimental group starting in kindergarten, 48 percent remained in the experiment for the entire four years” – a factor that undoubtedly affected results.

New analysis from researcher Spyros Konstantopoulos at Northwestern University, out this month in Elementary School Journal, provides an evaluation of STAR data and achievement gaps. According to Mr. Konstantopoulos, “reductions in class size did not reduce the achievement gap between high and low achievers” in the STAR program.

Data presented on Monday at the annual meeting of the American Educational Research Association will likely add to the complexity of the class size debate.

According to the March 25 edition of Education Week, a British study presented at the conference found clear benefits from class size reduction, noting that students in larger classes were “off-task” more frequently than pupils in smaller classes. But a Hong Kong study, also presented at the meeting, found smaller classes had “no effect on the level of student engagement,” notes Education Week.

What about North Carolina? Class size reduction here has been a key policy priority. But it hasn’t boosted achievement. Final data from the four-year, $23 million High Priority Schools Initiative (targeting low-income and low-performing elementary schools), showed “no statistical evidence that smaller class sizes raised student achievement,” according to Locke Foundation education analyst Terry Stoops.

Class size reduction programs present us with a policy conundrum. Common sense would seem to dictate that smaller classes are best. And in some cases, small classes work quite well. But research shows they’re not the panacea for anemic student performance many people believe them to be. What should we do?

Rather than mandating across-the-board class size reductions, we ought to take another look at research on achievement. Unlike class size data, research on teacher quality is unequivocally clear: teachers, more than any other school-based factor, have the greatest impact on student performance. In a 2003 Los Angeles Times op-ed, Eric Hanushek writes,“The difference in benefits gained from a good teacher (even in a large class) and a mediocre one (even in a small class) is far larger than any difference produced by class size.”

Effective teachers also help eradicate achievement gaps. According to landmark 1996 data from researcher William Sanders, “as teacher effectiveness increases, lower achieving students are the first to benefit,” although good teachers help students at all achievement levels.

There’s a lot more we can do to encourage teacher quality. We ought to start by changing our incentive structure. Value-added systems that track student performance over time showcase teaching prowess. Reforms like merit pay acknowledge and reward the educational value of our best teachers. And flexible alternative licensure and lateral entry routes help attract qualified mid-career professionals to teaching – a boon for districts facing teacher shortages.

In the end, though, here’s what we know for sure: when it comes to student achievement, the teacher in front, not the size of the class, matters most.

Kristin Blair is a fellow at the North Carolina Education Alliance This article originally appeared in The K-12 Update that she assembles for the NCEA.