From Valerie Strauss's WP blog and posted by guest blogger Susan H. Fuhrman:
The Obama administration’s “Blueprint for Reform” of the Elementary and Secondary Education Act encourages states to evaluate teachers based in part on their students’ scores on standardized tests. It is likely, then, that linking teacher evaluation to student achievement will play a significant role in upcoming policy initiatives and renewal of ESEA, the federal law more commonly known as No Child Left Behind.
In order to ensure fairness, most plans to evaluate teachers based on their students’ performance attempt to control for differences among students and other factors that are beyond the teachers’ control. They use the so-called “value-added” approach.
Recently, the National Research Council and the National Academy of Education jointly issued a report on value-added approaches, based on findings from a November 2008 workshop funded by the Carnegie Corporation of New York. According to the report, value-added models refer to sophisticated statistical techniques that measure student growth. They use one or more years of prior student test scores, as well as other background data, to adjust for pre-existing differences among students when evaluating student test performance.
Carnegie workshop participants were very cautious about using value-added measures for high-stakes decisions, such as salary and tenure rulings, which affect individual teachers. One reason is that a large number of teachers have students who are not given standardized tests.
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