Today’s post will wrap up my discussion of common misconceptions about value-added systems.

Criticism 8: The study shows that students in the 1990’s were doing quite well without test-based accountability–i.e., students were doing just fine before NCLB.

Response 8: This criticism is specific to Strauss, but I can’t find justification for it in the study. The study shows that students who were lucky enough to have an effective teacher were more likely to be successful after high school than students who had ineffective teachers. Keep in mind, study after study has shown that, especially in the 90’s, low-income and minority students were more likely to have ineffective teachers while higher-income and white students were more likely to have highly effective teachers. What this study shows is if those low-income and minority students had had teachers with high value-added scores instead of teachers with low value-added scores, they would have been more likely to go to college, earn a higher income, and save more for retirement today. Some students may have been “doing well” — but certainly, all students weren’t. So no, the study doesn’t show that students were doing quite well in the 1990′s; as a matter of fact, it shows many could have done much better if they were more likely to have a highly effective teacher.

Criticism 9: The study doesn’t validate the current use of value-added measures to evaluate teachers.

Response 9: It’s true that how value-added measures are used matters immensely. However, the study provides strong evidence that value-added measures can be an accurate tool to identify teachers who positively impact students’ future outcomes.

My take: Although value-added measures are not perfect, when used correctly — that is, along with other measures of teacher effectiveness within a comprehensive teacher evaluation system – the measures can effectively identify effective and ineffective teachers. This study reinforces that conclusion. And value-added measures are definitely more effective at predicting which teachers actually improve their students’ outcomes than how teachers have been evaluated traditionally. Instead of mistakenly resisting value-added measures, I’d like for critics to suggest ways to improve the evaluation system. Our students would benefit. – Jim Hull