The book Made to Stick: Why Some Ideas Survive and Others Die recounts a study in which a group of “tappers” was tasked with tapping out the rhythm to 120 commonly known songs and a group of “listeners” was supposed to guess what songs were being tapped out.
Before the experiment, the tappers estimated that the learners would guess half the songs. They actually guessed two percent.
The authors, the Heath brothers, call this the Curse of Knowledge. That is, if we already know something, we have a difficult time imagining not knowing it. The tappers knew what song they were tapping, so they thought it would be obvious to a lot of people.
Teachers face the Curse of Knowledge every day. Maybe we have taught the scientific method for 20 years so we can’t imagine it would take more than a review before we move on. Maybe we have read The Great Gatsby so many times we can’t imagine the students can’t see the Holy Grail motif. Maybe we have solved this exact equation so many times we can do it with our left hemisphere tied behind our backs.
So we present the material, and we expect the students to understand it. We tap out the song, and we hear it in our head, so we imagine everyone else can hear it too.
If I looked at my practice, I bet I’d see too much tapping, and not enough teaching.
How can I combat this? 1) We make my lessons “sticky.” That is, make them simple, unexpected, concrete, and rich with stories/anecdotes as good examples. 2) Check for understanding OFTEN. 3) Ask students to teach each other. This helps by A) making sure the “teacher” knows it, and B) making sure the “teacher” is a peer who might know better what makes a lesson sticky for another teenager.