Problems with Value-Added Teacher Evaluation in Secondary Schools

In this Education Week article, Stephen Sawchuk reports on two new studies that question the accuracy of value-added teacher evaluation in middle and high schools. What undermines the validity of value-added data, say the studies, is students being grouped by achievement. Value-added analysis compares a statistical estimate of students’ projected growth with their actual performance with each teacher, but tracking skews the data, making it difficult to use the data to distinguish between effective and ineffective teachers. 

For example, the same teacher can get a higher value-added score simply by teaching upper-track courses. In one of the studies, between 30 and 70 percent of teachers wound up in a different performance quartile after taking into account the courses they taught. At the high-school level, when researchers controlled for tracking, it became impossible to distinguish between high- and low-performing teachers in Algebra 1 and English 1 classes. There’s the additional problem of different schools having different criteria for grouping students.

“We know there are other ways in which we could be spending our energy to improve student outcomes,” said Kirabo Jackson, the author of one of the studies. “My takeaway is that this is not it.” 

“‘Value Added’ Use at Secondary Level Questioned” by Stephen Sawchuk in Education Week, Oct. 24, 2012 (Vol. 32, #9, p. 6); the studies in question are:

• “Bias in Public Sector Worker Performance Monitoring: Theory and Empirical Evidence from Middle School Teachers” by Douglas Harris and Andrew Anderson;

• “Teacher Quality at the High School Level: The Importance of Accounting for Tracks” by Kirabo Jackson; http://www.edweek.org/ew/articles/2012/10/24/09tracking_ep.h32.html

From the Marshall Memo #458