The learning-by-teaching effect has been demonstrated in many studies. Students who spend time teaching what they’ve learned go on to show better understanding and knowledge retention than students who simply spend the same time re-studying. What remains unresolved, however, is exactly why teaching helps the teacher better understand and retain what they’ve learned.
For a new study in Applied Cognitive Psychology researchers led by Aloysius Wei Lun Koh set out to test their theory that teaching improves the teacher’s learning because it compels the teacher to retrieve what they’ve previously studied. In other words, they believe the learning benefit of teaching is simply another manifestation of the well-known “testing effect” – the way that bringing to mind what we’ve previously studied leads to deeper and longer-lasting acquisition of that information than more time spent passively re-studying.