Sidney D’Mello, an assistant professor of computer science and psychology at the University of Notre Dame, does research into what teaching strategies induce learning. 

His research program looked for facial cues that would indicate confusion. After running various scenarios, the researchers found that confusion actually helped some students understand the material better.  Confused students learn better!

Confusion can provide a helpful jolt.  “That’s what emotions do—they direct attention. They tell you something is wrong with your world.”