Interleaving: How it rocked my (teaching) world - Alice Bell

I’ve never really written anything before about how or what I teach but Hazel had put a blog up on the Aquinas Hub and told me that I should do the same because I have for the last few months constantly been going on about some educational research which has rocked my (teaching) world. 
In 25 years of teaching, there have been only really been 3 things which have made a fundamental impact on how I think.  The first was a maths conference in my first year of teaching when I had the pleasure of hearing Dylan William speak about his work on assessment.  I was totally blown away by his philosophy and ideas. 
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The second thing was reading a book back in about 2003.  I really read it as a parent but it also fundamentally changed the way in which I communicate with students.  I reread it every couple of years just to remind myself. It’s called “How to Talk so Kids will Listen and Listen so Kids will Talk” by Adele Faber and Elaine Mazlish and I would highly recommend it for some light holiday reading. 
The third thing that has had a huge impact on my teaching is the one I want to talk about here.  Many of you will know that I play the cornet and I stumbled across an article - https://bulletproofmusician.com/why-the-progress-in-the-practice-room-seems-to-disappear-overnight/    Who would have thought that 18 months later this article, which introduced me to the ideas of interleaving, would have had such a huge impact not only on my playing but more importantly on my teaching.  And with the introduction of linear A levels its impact on learning is going to be even more important. 
 
So what is it interleaving all about?
I’ve always been taught as a mathematician and a “musician” that practice makes perfect.  Keep going through the technique and the more questions you do the better you get.  And that is what I always told my students.   Many of my students though wouldn’t be able to answer a question in the exam despite all their practice.  I knew the same happened with my music practice.  I’d have mastered that really tricky passage the night before but then when I came to play it at the actual rehearsal it was as if I had never seen it before.
Reading this article it pointed out that “constant repetition is boring and our boredom is telling us that our brains are not engaged”. Essentially all that practice time is wasted once our brains have switched off.  We are no longer learning and it is learning that is the important thing.  It seemed really obvious but I had never thought of it like that before.  The article contrasted “blocked practice” where we do the same thing over and over again with “random practice” where we mix up what we are practising.  For example instead of doing 20 questions on quadratic equations in a row followed by 20 questions on algebraic fractions then 20 questions on integrations, we could do 2 questions on quadratics, followed by 1 on fractions, then 2 on integration and followed by another 1 on fractions etc etc.  The examples in the article focused on sport as well as music but not really on Maths.
The research shows that, although a blocked schedule produces superior performance during the practice, it produces poorer retention a day or more later.  I got to thinking that this could be why my students were telling me they could do it for homework but then couldn’t reproduce it in the exam.  The article went on to explain that interleaving or random practice means that you must “construct and later reconstruct an action plan” every time and it is this that improves your learning.  Intrigued, I started to research further and there were many articles specifically relating to how Maths is taught and the benefits that interleaved practice can bring. 
 
How did I start to use it in my classroom?
I started to introduce this in my classroom last year with my Lower Sixth classes with the work that I set them. This meant breaking down the way in which they had always been taught to practise maths, where most text books have exercises that essentially repeat the same skill over and over.  The new method required more independent learning from them so I checked their work each week to monitor what questions they were doing.  There were some who found it difficult to mix up their questions and still clung to their old way of working, doing a whole exercise of repetitive questions.  Inevitably these were the students who were not performing as well in assessments but needed the security blanket of feeling they “could do the maths”. In reality they were just wasting a lot of time, as their brains switched off and they stopped learning.    
This year I have gone for it in a big way with all my A level groups, playing them the video link in the article so they could understand the rationale behind the method.  It was also a perfect opportunity to introduce them to neuroscience, which links into careers and progression with a bit of cross curricular Psychology in there.    I have also changed the structure of my lessons so I switch between topics more regularly.  I will throw in a question on an old topic for them to do, so that when we come back to the new topic they have to once again construct their action plan.  This does make the lessons more engaging as they are constantly having to recall and remember previous methods.  It also allows for better linking between topics. 
 
So does it really make a difference?
It’s almost impossible to give a definitive answer on cause and consequence in teaching as so many variables change.  However, I do know that my ALPS grades for my lower sixth groups went up significantly last year.  I do know this year that many of my students really bought into it and practised interleaving in their independent study.   I also had a couple of parents ask me about it at parents’ evening because their children had been talking to them about it at home. 
What I don’t know is whether it will have made a difference to student outcomes this year.  The ALPS scores based on their mock exams are a positive sign but of course it is the real thing that counts and I won’t know that till August. 
On a personal level the way I now do my music practice has made a difference to my playing.  Several of my friends have commented (with surprise) about how much progress they’ve noticed in my playing.  If interleaving in Maths has given my students that extra confidence and success so they can feel good about themselves too then it’s definitely been worth it. 
I have no doubt that other departments and teachers are doing similar things.  I know there were other people in the Maths department who were already mixing up the questions that they set because it seemed to be having a positive impact.  Up until about 18 months ago, however, it had really passed me by.  I followed the usual maths textbook approach of 20 of the same question one after the other which is something I had always done.  Stumbling upon that article captured my imagination.  Interleaving really does make sense to me and will possibly become even more important with the new linear A levels. 
I love a bit of evidence based research, interleaving has had a huge impact on my teaching and is now my underlying philosophy for how I teach.  It really has rocked my world.  

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