For more than a decade, economist Ronald Ferguson has studied achievement gaps. In 2002, he created the Tripod Project for School Improvement, a professional development initiative that uses student and teacher surveys to measure classroom conditions and student engagement by race and gender. He spoke with the Harvard Education Letter about the most recent findings from the Tripod Project surveys.

How do you define “achievement gap”?

There are a lot of different achievement gaps. The achievement gap that I focus the most on is the gap between students of different racial groups whose parents have roughly the same amount of education. It concerns me that black kids whose parents have college degrees on average have much lower test scores than white kids whose parents have college degrees, for example. You can take just about any level of parental education and we have these big gaps.

How much progress has been made in closing black-white achievement gaps?

Huge progress since 1970, not much progress since 1990. Sixty-two percent of the overall black-white reading-score gap for 17-year-olds disappeared between 1971 and 1988. About one-third of the math-score gap disappeared during the same period. Over the last several years the gap has narrowed significantly for both 9- and 13-year-olds, but there’s been a bit of backsliding for the older teens.

There’s been enough progress to establish firmly that these gaps are not written in stone.