What does the data tell us?

(1) While racial gaps subsided from 1950s-80s, the overall socio-economic gap is mostly unchanged over the past half-century.  National programs to improve the education of disadvantaged students, while perhaps offsetting a decline in the quality of teachers serving such students, have done little to close achievement gaps.

(2) The overall achievement gains realized by students at age 14 fade away by age 17, yet policymakers have left high schools—like the achievement gap itself—in many ways untouched.

(3)Teacher effectiveness is a predominant factor affecting school quality.  Teacher salaries have declined relative to those earned by other four-year college-degree holders and are currently low relative to comparable workers in other occupations. Collective-bargaining agreements and state laws have granted more-experienced teachers seniority rights, leaving disadvantaged students to be taught by less-effective novices. A growing disparity in teacher quality across the social divide may have offset the impacts of policies designed to work in the opposite direction.

The Achievement Gap Fails to Close

Half century of testing shows persistent divide between haves and have-nots

Eric Hanushek, Paul Peterson, Laura Talpey and Ludger Woessmann

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