For instance, the character strength of self-control is assessed by questions about whether students “came to class prepared” and “allowed others to speak without interrupting”; gratitude, by items like “did something nice for someone else as a way of saying thank you.” The frequency of these observed behaviors is estimated using a seven-point scale from “almost never” to “almost always.”

Most students and parents said this feedback was useful. But it was still falling short. Getting feedback is one thing, and listening to it is another.

To encourage self-reflection, we asked students to rate themselves. Thinking you’re “almost always” paying attention but seeing that your teachers say this happens only “sometimes” was often the wake-up call students needed.

This model still has many shortcomings. Some teachers say students would benefit from more frequent feedback. Others have suggested that scores should be replaced by written narratives. Most important, we’ve discovered that feedback is insufficient. If a student struggles with “demonstrating respect for the feelings of others,” for example, raising awareness of this problem isn’t enough. That student needs strategies for what to do differently. His teachers and parents also need guidance in how to help him.

Scientists and educators are working together to discover more effective ways of cultivating character. For example, research has shown that we can teach children the self-control strategy of setting goals and making plans, with measurable benefits for academic achievement. It’s also possible to help children manage their emotions and to develop a “growth mind-set” about learning (that is, believing that their abilities are malleable rather than fixed).

This is exciting progress. A 2011 meta-analysis of more than 200 school-based programs found that teaching social and emotional skills can improve behavior and raise academic achievement, strong evidence that school is an important arena for the development of character.

But we’re nowhere near ready — and perhaps never will be — to use feedback on character as a metric for judging the effectiveness of teachers and schools. We shouldn’t be rewarding or punishing schools for how students perform on these measures.