Principals Reject ‘Value-Added’ Assessment That Links Test Scores to Educators’ Jobs

The Board of Directors of the National Association of Secondary School Principals has given preliminary approval to a statement that rejects linking educators’ jobs and pay to standardized test scores that are plopped into a formula that can supposedly determine exactly how much “value” an individual educator has added to students’ academic growth.

The method of linking test scores to job status and pay is known as “value-added measurement” or VAM, and it has been embraced by school reformers, including the Obama administration, as a prime way to hold educators “accountable” for how well their students do in class. In some states, up to 50 percent of an educators’ evaluation is based on VAM systems. The problem is that numerous assessment and statistics experts — including the American Statistical Association — have said that VAM formulas (there are many) are not a valid or reliable method of assessing the value of individual teachers and principals.

Last April, the Statistical Association, the largest organization in the United States representing statisticians and related professionals, said in a report that value-added scores “do not directly measure potential teacher contributions toward other student outcomes” and that they “typically measure correlation, not causation,” noting that “effects — positive or negative — attributed to a teacher may actually be caused by other factors that are not captured in the model.” After the report’s release, I asked the Education Department if Education Secretary Arne Duncan was reconsidering his support for value-added measures, and the answer was no.

Read more at the Washington Post