Student achievement on standardized test should not be considered in teacher performance evaluations. Research tells us that teachers vary enormously in their ability to improve students’ performance on standardized tests but that many existing teacher evaluation and reward systems do not capture that variation. Students are randomly placed with a teacher. It wouldn’t be fair to base it on the teacher’s performance, because all students are different and learn in different ways. Some students are smarter than others, and others may have problems learning.
There is another reason why it shouldn’t be considered. In a growing effort to recognize and reward teachers for their contributions to students’ learning, many states are remaking their teacher evaluation systems to improve measures of student performance. This trend stems from evidence that teacher evaluations and reward structures have not sufficiently distinguished teachers who are more effective at raising student achievement from those who are less effective.
Although schools want to find ways for this to work, this next fact just proves to be another reason why it shouldn’t be considered. Policymakers are increasingly attempting to base a portion of teachers’ evaluations or pay on student achievement gains. However, systems that incorporate student achievement gains into teacher evaluations face at least two important challenges: generating valid estimates of teachers’ contributions to student learning and including teachers who do not teach subjects or grades that are tested annually.
Schools are not ready for this. As of now, student achievement on...