Interleaving
Jonathan Firth's Memory & Metacognition Updates #14
Hello, and welcome to another issue of my memory and metacognition updates.
I've been thinking about how to make these updates as valuable as possible to you, bearing in mind that while the bulk of readers are based in schools, many are in universities or other settings.
Fortunately, a lot of what I write about is pretty broadly relevant. Issues around memory and metacognition apply internationally, regardless of the curriculum studied. Certain principles and strategies remain consistently useful, regardless of the subject or age group, and to the workplace, too.
This was the conclusion of my systematic review into interleaving. I won't share the review here as it's pretty long, but the main conclusions are summarised in the 'context and implications' document linked below.
bera-journals.onlinelibrary.wiley.com — bera-journals.onlinelibrary.wiley.com
Context and Implications Document for: A systematic review of interleaving
To summarise even more briefly, interleaving means varying the order of examples or tasks, so that learners see contrasting types of items together. This differs from the standard educational practice, where students are given sets of practice problems that all illustrate the same thing.
The idea is that seeing how things differ helps learners to develop their conceptual knowledge. They need to know what something is not, rather than just what it is.
In other words, they need to know the boundaries of a concept.
To take an everyday example, if a child is learning what an oak tree looks like, it would be useful to see some oak trees as well as some trees that are not oaks, in order to illustrate the differences.
This is an idea that can be applied to classrooms at every age and stage. The main difference for more advanced learners is that the differences that they notice become more subtle.
A good paper that discusses this concept is by Carvalho & Goldstone (2015). It's a bit technical in places, but highlights some important points, such as the idea that interleaving is not due to the spacing effect, and that how similar a set of items are can help to determine whether we should interleave or not.
The key takeaway is as follows:
If a set of items are subtly different, it would be best to interleave them, so that learners notice the differences.
If the set of items are very different, learners might actually find it hard to notice the similarities, rather than the differences! To see what such items have in common, it would be best to study them in a 'block', rather than to interleave.
Hopefully these point shows that while the benefits of interleaving, are certainly powerful, they do require some professional judgement and awareness of the key issues, both in terms of the material and the learners themselves.
It's not a technique that we can always apply to every situation, but rather a part of an educator's professional toolbox.
I'll mention interleaving again next week when I discuss Dunlosky et al's famous list of evidence-based strategies. You can also find my 'interleaving chat' YouTube video with Innerdrive linked in issue 5 of this newsletter.
If you have follow-up questions, do feel free to reply to this email!
That's it for now, all the best,
Jonathan