What is Interleaving?
Interleaving is a learning strategy that involves mixing up different topics or skills during your study sessions. Instead of spending an extended period on a single topic, you rotate between related subjects, concepts, or problem types. This approach might seem counterintuitive at first, but research has shown that it significantly enhances long-term retention and application of knowledge.
I’m guilty of not making use of this powerful revision strategy when studying for exams during my school and university days. I remember focusing on single topics one at a time until I felt I had mastered each one. For example, splitting my revision days into three sessions (morning, afternoon and evening), I would either study a different topic in each session for hours at a time, or change the type of task that I was doing (e.g. reading/taking notes, trying past paper questions etc) but for the same topic. Not only have I learned that rereading notes is a hugely ineffective way of revising, I now realise that both scenarios described above actively go against the idea of Interleaving.
One could be forgiven for thinking that studying topics in blocks is more logical and makes more sense. However, the research shows that switching between ideas during a study session is way more effective at helping you to understand and remember the information in the long run. Another advantage is that it helps to prevent boredom during a study session due to the nature of changing topics or tasks.
How does Interleaving work?
When you study the same material over and over again in a blocked manner, it's easy to fall into the trap of recognising patterns and memorising facts without deeply understanding the underlying concepts. Interleaving disrupts this passive learning process by introducing variability. When you switch between different topics, your brain needs to actively retrieve and reconstruct the information each time, strengthening the neural connections related to that knowledge.
The Learning Scientists (https://www.learningscientists.org/) have produced a good summary of how Interleaving works, as shown below.
Practical Tips for Studying with Interleaving
Mix it up, but keep it related: When practicing interleaving, choose subjects or skills that are related to each other. For example, if you're studying physics, you could switch between Newton’s Laws of Motion, Projectile Motion and Conservation of Energy. This way, you still maintain a cohesive study session while benefiting from the interleaving effect.
Short bursts of practice: Instead of focusing on one topic for an extended period, break your study time into shorter chunks. Dedicate 20-30 minutes to a specific subject before switching to another. This frequent switching encourages active retrieval and helps reinforce the material more effectively.
Embrace challenges: Interleaving can be tough, especially when you're faced with diverse topics in quick succession. Embrace the challenge! The difficulty of the task is a sign that your brain is actively engaged in the learning process, leading to more substantial and long-lasting learning gains.
Regularly revisit past material: To maximise the benefits of interleaving, make sure to revisit previously studied topics at spaced intervals. For example, if you've covered a particular chapter or concept, come back to it after a few days or weeks. This spaced repetition further strengthens your memory and cements your understanding.
Use active learning techniques: Incorporate active learning strategies while interleaving. Quiz yourself on each topic, engage in discussions, or solve problems related to different subjects. These activities stimulate your brain to retrieve and connect information, enhancing your overall learning experience.
Remember, the key to effective interleaving is striking a balance between mixing up topics and maintaining a coherent study plan. Don't be discouraged if it feels challenging initially; with practice, you'll discover the immense benefits of this technique.
Source: Cajun Koi Academy (YouTube)