Walking home late at night, a man finds his neighbor searching for something under a street lamp and stops to help. “What have you lost?” the man asks. “My wedding ring,” the neighbor replies. “Are you sure you dropped it here?”

“No,” the neighbor answers. “I dropped it over there, but it’s dark over there and light over here. I am searching where I can see.”

This ancient and well-worn fable is, unfortunately, an apt description of a great deal of research on the characteristics of highly effective teachers. Previous work on this topic, including some of my own, focuses on information already being collected by school districts and state boards of education, such as whether teachers possess graduate degrees, obtain special certification, or have a degree from a selective college. But to the frustration of many, these “highly qualified” teachers are typically no better than their less-decorated colleagues, or not nearly as effective as one might hope, given that we hire and pay teachers based on these attributes.

In a recent study, my colleagues Thomas Kane from Harvard University, Brian Jacob from the University of Michigan, Douglas Staiger from Dartmouth College and I try to shine a new light on this topic. To do that, we surveyed hundreds of new math teachers in New York City and collected information on a number of non-traditional predictors of effectiveness, including specific content knowledge, cognitive ability, personality traits, feelings of self-efficacy and scores on a commercially available teacher-selection test. We then looked to see whether teachers who scored higher on these measures also led their students to higher gains in math achievement on standardized exams.

Our first finding was that none of the single measures we studied is a very strong predictor of student outcomes. In other words, there is no silver bullet, no pencil-and-paper test that will tell you exactly how good a prospective teacher will be in the classroom. However, we also found that the measures we collected can be used to build broader indices of cognitive and non-cognitive skills. Moreover, by pooling individual measures into indices, one gains modest, but statistically significant, predictive power to predict which teachers will be more effective than others.

Through low-cost mechanisms, such as our online survey, school officials can gather an expanded set of information on candidates to help them use their resources more effectively. Districts can do their own analyses to see which teachers tend to perform well, and can focus their efforts on increasing the pool of candidates with similar traits. Individual schools could use this information to decide the order in which to interview candidates or the particular issues they focus on during the interview process.

Researchers and policymakers agree that hiring good teachers is one of the most promising paths to improving school quality. But, if we want to find a new supply of great teachers, we need to change methods by which we search for them. Like the lost wedding ring, we might just be surprised with what we find.

Photo credit: Liz Marie