"Value-added" rankings have been a buzz word among educators since "Race to the Top", began promising funds to school systems that adapt to certain requirements, such as evaluating teachers' performance by using factors like student achievement.
The approach has sparked a heated debate among government officials, teachers, union representatives, lawyers and researchers about the validity of this evaluation methodology.
Those who support using the "value-added" method argue that it's impossible to measure the teachers' quality without factoring in student achievement. Secretary of Education Arne Duncan mentioned, those who oppose it argue the methodology is deeply flawed and that different value-added models produce contradictory and unstable conclusions.
Daniel Koretz, a Harvard professor whose research contributed to persuading states to raise standards, told The New York Times that it's "impossible" to know whether rising scores in a classroom are a result of inappropriate test preparation or real learning improvements.
Aside from the certainty that this method of evaluation is here to stay -- several states have already adapted to the requisites in order to qualify for more funds -- there's another sure thing: Everybody, even those who defend the approach, agree that it shouldn't be the only factor for measuring teachers' quality.
Classroom observations or talking periodically to the students or parents should also be considered in the equation.
Douglas Staiger, an economics professor at Dartmouth College, told The New York Times:
"This information is useful but has to be used with caution," he said. "It's that middle ground. It's not useless, but it's not perfect."