Feature Story

July 5, 2007

Has Student Achievement Increased Since No Child Left Behind?

Center on Education Policy:

Student achievement in reading and math has increased since the No Child Left Behind Act was enacted in 2002, according to the most comprehensive and thorough study to date of the results of state tests administered as part of the landmark federal education law.

The study is unique as it includes verified data from all 50 states -- much of which is available for the first time in the report -- and investigates achievement trends both before and after the passage of NCLB.

The report also limits its analysis to testing data that is comparable from year-to-year, eliminating data in grades and subjects where states have made significant changes to their assessment systems.

The report also uses two methods for evaluating achievement, including the percentage of students considered proficient -- the primary measure of adequate yearly progress under NCLB -- and effect sizes, a measure based on average test scores that addresses some of the limitations of the percentage proficient measure.

Using either method, the report finds that the number of states showing achievement gains since 2002 is far greater than the number showing a decline.

Using the percentage of students reaching proficiency and effect sizes, the report finds that the biggest improvements since 2002 were seen in elementary level math, where 22 of 25 states with comparable data demonstrated moderate-to-large gains on both measures, and no state showed a moderate-to-large decline.

There is more evidence of achievement gaps narrowing than widening since 2002, though gaps remain substantial.

CEP found that complete data on the percentage of students proficient were available on the Web in just 25 states.