Reflections on The Science of Memory - Spaced Practice

The Learning and the Brain conference is an overwhelming experience.  That’s not a complaint.  It’s the best professional development I’ve ever participated in.  It’s overwhelming in the way a magnificent artwork is overwhelming, just too much to take in.  It’s overwhelming in the way meeting a beloved public figure would be overwhelming, just wanting to remember every part of the moment but also knowing that you won’t.  I have attended this conference twice now, and I have come away both times with the same mixture of feelings.  First, I feel mostly affirmed that much of what I and my colleagues are doing is in line with how student's brains work.  Even though much of it has been developed through trial and error or intuition, we seem to have done a lot right.  Second, there are some changes we need to make to some of our practices.  Holding those two thoughts simultaneously weighs down my luggage on the trip home.

The only way I have found to deal with the sheer volume of information I get from this conference is to reflect on parts of it a little at a time while I figure out how I might like to apply them.  Since this blog is for me to reflect and process my thoughts and let you read them if you wish, I’ll be dealing with those here for a while. They might come out in weekly posts or I might post several over the course of a few days.  Who knows?  If you just want straightforward notes (with a few personal thoughts because that’s how I take notes), you can find them at these three posts (Friday, Saturday, Sunday).  These posts will be both more and less than the notes.  More because I will be working out my own thoughts but less because I will likely choose small parts to reflect upon.

I started reading about this over the summer in the book Powerful Teaching by Pooja Agarwal and Patrice Bain.  While I don't recommend reading the book from beginning to end (the writing is distracting because they make jokes that don't work in text and over-use exclamation points at an alarming rate), I totally recommend going to the end of each section and using the techniques.  It is based on the current research into remembering and forgetting and advocates for a concept known as Retrieval Practice.  This concept came up in at least four different sessions at the Learning and the Brain conference because it is powerful.  To be most effective, it should be

• Spaced
• At a level of desirable difficulty
• Mixed (interleaved)

Spaced - We all know that cramming is a bad idea if we want long term learning.  It may help you perform well on the quiz you have 10 minutes from now, but it will not help anything go into long term memory.  Adults, you know this.  The all-nighter may have helped you pass the test the next day (although you kind of cancel it out from the lack of effect that sleep has on memory development), but you probably don't still know the stuff you studied that night.

Spaced retrieval is the most effective way to study, and increasing the spacing each time is necessary.  If you teach something on a Monday, ask a few questions on Tuesday.  Your students will probably remember it well, but that is misleading.  It hasn't been long enough for spaced retrieval practice to be helpful.  Wait until Thursday before asking again.  The weird key is that you want them to have ALMOST forgotten it but not quite.  Only you can use your professional judgment to figure out the exact spacing that works for your class.  If they answer really quickly, you haven't waited long enough.  If they have to go look it up, you have probably waited a day too long.

The diagram below is a powerful illustration of how much you retain with each spaced review. 

 

As you can see, the forgetting curve gets shallower with each revisiting of the material.  A line connecting the dots of each revisit becomes a remembering curve.

Desirable Difficulty - As teachers, we often want to make things easier for our students.  Their parents certainly want us to do that.  The problem is that our brains don't remember things that are easy to learn.  When you have to search around for the answer, you tell the brain that remembering this is worth the effort you are putting into it.

Again, this is a matter of professional judgment and experience.  We always know when we have made something too hard.  It's not from student complaints; in fact, if you never get complaints about your level of difficulty, it is probably a sign that you have made things too easy.  We know it is too hard when a student cannot proceed at all, not even with a little prompting.  It's harder to diagnose too easy, but the guiding principle is this.  There should be some need to think, some little bit of searching to remember.  

Interleaved - I used to do this wrong.  I taught velocity on Monday and gave velocity problems for homework.  I taught acceleration problems on Tuesday and gave acceleration problems for homework.  Then my school instituted a policy that we would only have homework in a class for a maximum of three nights each week (exceptions for math and AP classes).  I already couldn't give homework on Wednesdays (Christian school), so I had to figure out a way to consolidate some assignments.  (It sounds like I give a ton of homework, but I promise I don't.  Some things that require it (like math practice) just end up near each other in the same week.)

To deal with this issue, I started consolidating homework assignments.  I began teaching two or three concepts and then giving a homework assignment with mixed practice on all three.  What I had stumbled upon was a better understanding of how to choose the right equation to solve the problem.  When I first read an article about interleaving, I realized that I had accidentally done was a research-proven method.

After reading this, I started teaching it to students as a study method.  Shuffle your flashcards between each round.  Better yet, flip it around and put it back at a random spot in the deck.  Based on the suggestion of the book Powerful Teaching, I have a basket of questions in my room that I add to with each chapter.  When we have those five minutes of time you sometimes get at the end of a class, I pull them out and start randomly asking them.  Sometimes, we play it family feud style with a bell.  The spacing is a little random, and the method of pulling them from a basket automatically mixes them.  Sometimes at the beginning of class, I'll ask students to take out paper and write down five things they remember from the day before or the week before.

We are all pressed for time, but we usually have a few minutes here or a bellwork there that we can use for retrieval practice.  Since we know it has powerful effects, we should take advantage of that time.