For example, in 2009, 90 percent of fourth graders in Tennessee met their state's proficiency standard for reading. But students also take the National Assessment of Educational Progress, or NAEP. It's a federal test that also evaluates student reading. The NAEP found that just 28 percent of Tennessee fourth graders read proficiently. That's a massive difference.
"You can't explain that kind of difference," says then-governor of Tennessee Philip Bredesen, "by anything other than the standards we were measuring them against were just vastly softer and vastly easier."