Typically, achievement gaps between groups of students are measured as either differences in average scores or differences in proficiency rates. But, practitioners, policymakers, and researchers have long recognized that these approaches don't tell the whole story. Average scores, for example, are good at summarizing trends but can mask real…

This article provides examples of how serious misconceptions can result when only "all student" scores from the National Assessment of Educational Progress (NAEP) are used for simplistic state-to-state comparisons. Suggestions for better treatment are presented. The article also compares Kentucky's eighth grade EXPLORE testing to NAEP…

Because many school funding studies are seriously flawed, valid conclusions cannot be reached concerning the effects of school funding in the United States. New evidence from the National Assessment of Educational Progress and two international achievement tests shows that differences among U.S. public school districts (and states) in funding and…