Coming soon to an urban district near you…. (See full report here in
Washington Post Valerie Strauss’s blog.)
“The Cleveland Plain Dealer just published the “value-added” ratings of teachers that purport to show how effective a teacher is or isn’t. TheLos Angeles Times did something similar in 2010 and 2011, and so didThe New York Times in 2012. In every case the newspapers came under heavy criticism.
“Value-added ratings are derived by taking the standardized test scores of students and plugging them into a complicated formula that can supposedly determine how much “value” a teacher adds to a student’s achievement by taking into account a varying number of factors. How complicated? Here’s an example, taken from the website of the D.C. Public Schools: