Class-Size Reduction of Limited Value on Achievement Gap, Study Finds
It's probably true that high achievers would benefit more from such a setting. But why fret over gaps if both high and low achievers benefit from smaller classes? Just not at the same rate.
Reducing class sizes—a popular policy among parents, teachers, and lawmakers—has long been viewed as a way to increase student achievement.
But while shrinking the number of students in a class can lead to higher test scores overall, it might not necessarily reduce the achievement gaps that exist between students in a given classroom, a new study suggests.
Reviewing data from Project STAR—a longitudinal research study on class-size reduction in Tennessee and the most famous experiment on the topic—Spyros Konstantopoulos, an assistant professor of education and social policy at Northwestern University, in Evanston, Ill., said that it’s a “tempting” idea to think that having fewer students assigned to a teacher will reduce the achievement gaps between students.
Instead, he found, “manipulating class size” doesn’t appear to narrow those gaps. In fact, the range from the lowest achievers to the highest achievers—what he calls “variability”—was greater in the smaller classes of 13 to 17 children than it was in larger classes of 22 to 26 students. He came to that conclusion after looking at the performance of all students in the STAR study, as measured by the Stanford Achievement Test.
“In the present study, I found that high achievers benefit more from being in small classes than low achievers,” Mr. Konstantopoulos said in an e-mail. “This indicates that the achievement gap is larger in small classes than in regular-size classes.”
He suggests in the article, which is being published in the March issue of Elementary School Journal, that the higher achievers, perhaps, are better at taking “advantage of the opportunities or teacher practices that take place in small classes.”