June 12, 2000

June 12, 2000 | News Releases on Education

Small Class Sizes Don't Improve Student Performance, Study Says

WASHINGTON, June 12, 2000-The notion that smaller class sizes will automatically boost academic achievement has become a mantra for parents and politicians. But children in classes with 20 or fewer students scored no higher on a national reading test than students in classes with 31 or more students, says Kirk Johnson, an analyst with The Heritage Foundation's Center for Data Analysis.

Using data from the 1998 National Assessment of Educational Progress (NAEP) reading test, Johnson found that being in a small class does not affect reading achievement in any significant way.

It appears, Dr. Johnson said, "that class size … pales in comparison with the effects of many factors not included in the NAEP data, such as teacher quality and teaching methods."

Elementary and high-school class sizes are already smaller today than in the 1970s, due to demographic trends and policy efforts to improve student-teacher ratios. Today, public schools average about 17 students per teacher, down from 22.3 students per teachers in 1970. Yet academic achievement, as measured by the NAEP, has remained relatively constant.

The Department of Education's NAEP exam in core subjects is given every two years to fourth, eighth and 12th grade students nationwide. In one year, the students are tested in math (as they were in 1996), while the next exam tests reading. Johnson modeled the NAEP data on six factors: class size, race and ethnicity, parents' education, the number of reading materials in the home, participation in the free or reduced-price lunch program, and gender.

About the Author