Wanted: Ways to Assess the Majority of Teachers

The debate about “value added” measures of teaching may be the most divisive topic in teacher-quality policy today. It has generated sharp-tongued exchanges in public forums, in news stories, and on editorial pages. And it has produced enough policy briefs to fell whole forests.

But for most of the nation’s teachers, who do not teach subjects or grades in which value-added data are available, that debate is also largely irrelevant.

Now, teachers’ unions, content-area experts, and administrators in many states and communities are hard at work examining measures that could be used to weigh teachers’ contributions to learning in subjects ranging from career and technical education to art, music, and history—the subjects, in other words, that are...