Research shows that assuming a test scale is equal-interval can be problematic, especially when the assessment is being used to achieve a policy aim like evaluating growth over time. However, little research considers whether teacher value added is sensitive to the underlying test scale, and in particular whether treating an ordinal scale as…

In accordance with the federal No Child Left Behind (NCLB) law of 2001, 100% of students were expected to become proficient on state assessments of reading and mathematics by the end of 2013-2014 academic year. Schools that consistently failed to meet the NCLB's Adequate Yearly Progress requirements were subject to penalties. In 2011, the U.S.…