Over a hundred years ago the German psychologist Hermann Ebbinghaus (1885) came to this conclusion after painstakingly exposing his human subjects to list of words.   He also discovered that most of this forgetting occurs just hours after being exposed to the new material.  It is called the curve of forgetting.

When we encounter new information, neurons in our brain activate, but the stimulation lasts only up to 90 minutes unless it is reactivated (Squire, Kandel, 1999).  We begin to commit the new learning to memory when we first practice it, but for learning to endure in our memory, we must return to it at intervals and in different ways over weeks, months, and even years.

Quick Learning

A popular model in education is “teaching to mastery”.  We often interpret this to mean that students need to practice a language point intensely until it is burned into memory. Indeed, while students are practicing, they demonstrate an easy fluency with the material.  That is because it is active in their working memory.  Teachers and students alike prefer this intensive kind practice because it produces rapid, if ephemeral, gains. Quickly students gain confidence in their control of the material.  It feels familiar and known.  If tested immediately after intensive repetition and in a way that simulates the rehearsal, students score well.

Quick Forgetting

It turns out, however, that intensive repetitive practice leads to quick learning AND quick forgetting.  (Dunloskey, 2013).  If students are tested on that same material just a day later, their scores drop precipitously. The challenge is to have students put the material aside and then return to it. Inevitably they will have forgotten some of the material, and that is ok.  The effort they make to retrieve and reconstruct the information each time they practice it anew will strengthen their memory. Continue reading →