A Beginner’s Guide to Interleaving by Tanisha Paul

by Academic Skills Peer Coach Tanisha Paul

It’s common to feel frustrated when studying for extended periods. While sitting down for six hours straight to tackle that challenging physics problem might seem productive or necessary, it may not be the most effective approach. If you’re finding it hard to focus or concentrate after an hour or two, changing your study strategy might be key. The technique of interleaving can keep your brain engaged, making your study time more efficient and less mentally exhausting.

What is Interleaving?

Interleaving is a study technique that involves alternating between different subjects or problem types, rather than focusing on one topic for an extended period. This approach was developed based on research in cognitive psychology, which has shown that varying the material you study can enhance memory and problem-solving skills. Originally designed to help students retain information more effectively, interleaving encourages the brain to make connections between different ideas, leading to deeper understanding and long-term recall. It challenges the mind to adapt, rather than depending on repetitive practice.

Why Does Interleaving Work? (The Science Behind It)

Interleaving is grounded in cognitive psychology research that shows how the brain learns best when it is challenged to retrieve and apply information in diverse ways. When you alternate between different topics or problem types, your brain has to work harder to recall and apply new material, which strengthens neural connections. This process, known as “desirable difficulty,” might feel harder in the moment, but it leads to better long-term retention and understanding. By constantly interacting with different types of information, interleaving helps you build a more flexible and adaptable grasp of your subjects—making it easier to recall what you’ve learned when it really matters, like during exams.

How Can I Incorporate Interleaving Into My Study Schedule?

If interleaving is new to you, it’s okay to start gradually. Below are a few strategies to help you incorporate interleaving into your study routine in a way that feels manageable and effective:

1. Start by mixing similar subjects or topics.
   Instead of diving into completely unrelated subjects, try alternating between topics that are somewhat connected. For instance, if you’re taking a science course and a math course, you can alternate between reviewing concepts from one and practicing problems from the other. This way, your brain can make connections without the challenge of juggling unrelated subjects too soon. As you get comfortable, you can branch out to mixing different types of material, like alternating between science and humanities.
2. Set Time Limits for Each Topic.
   Rather than studying the same subject for hours on end, break your sessions into shorter blocks. You might spend 30-90 minutes reviewing lecture notes for one class and then switch to working on a different assignment or studying for a different class. Switching after short intervals helps your brain stay fresh and focused, making your study time more efficient without overwhelming you.
3. Alternate Problem Types Within a Subject.
   If switching between subjects feels like too much at first, try interleaving within one class. For example, if you’re preparing for an exam in a math or science course, mix different types of problems or concepts during your study session. Working through a variety of challenges keeps your brain engaged and builds a more flexible understanding of the material.
4. Use Interleaving During Review Sessions.
   When it comes time for exam prep, rather than reviewing all the material from one class in one sitting, alternate between different courses or topics. This could look like studying one chapter for one subject, then switching to a completely different topic from another class. This variety will keep you from burning out and help with long-term retention.
5. Find a System That Works for You.
   As you start incorporating interleaving, keep track of what works and what doesn’t. Maybe switching topics every 30 minutes feels too quick, or you find that certain subject combinations help you stay focused better than others. Tailor the method to your own learning style, adjusting the frequency and subjects to what feels most productive.

What if I’m “In the Zone”?

If you’re really immersed in studying for one subject and feel like you’re making great progress when your timer goes off, don’t feel pressured to switch right away. While interleaving can be an effective strategy, it’s important to use it in a way that works best for you. If you’re in a good flow with one subject, you can extend your focus and come back to interleaving once you’ve wrapped up that productive streak. The goal is to make your study time as effective as possible, so trust your instincts and use this technique at your own discretion.

Common Mistakes to Avoid

While interleaving can be a great tool for learning, it’s important to avoid a few common pitfalls: Switching too frequently between topics can leave you feeling scattered and prevent comprehensive understanding, so make sure to give yourself enough time with each subject before moving on. Another mistake is rushing through material without fully grasping it—interleaving is about challenging your brain, not speeding through your study sessions. Finally, don’t forget to review older topics regularly. Just because you’ve moved on to a new subject doesn’t mean you won’t need to refresh your memory later. Effective interleaving requires balance, patience, and consistency.

References

Carvalho, P. F., & Goldstone, R. L. (2014). Effects of interleaved and blocked study on delayed test of category learning generalization. Frontiers in Psychology, 5(936). https://doi.org/10.3389/fpsyg.2014.00936

Converse, K. (n.d.). What’s the Difference Between Interleaving and Spaced Retrieval? https://explore.medstudy.com/blog/difference-between-interleaving-and-spaced-retrieval

Ferlazzo, L. (2021, May 30). The What, Why, and How Of “Interleaving” (Opinion). Education Week. https://www.edweek.org/teaching-learning/opinion-the-what-why-how-of-interleaving/2021/05

Hulbert, J. C., & Norman, K. A. (2014). Neural Differentiation Tracks Improved Recall of Competing Memories Following Interleaved Study and Retrieval Practice. Cerebral Cortex, 25(10), 3994–4008. https://doi.org/10.1093/cercor/bhu284

Pan, S. C. (2015, August 4). The Interleaving Effect: Mixing It Up Boosts Learning. Scientific American. https://www.scientificamerican.com/article/the-interleaving-effect-mixing-it-up-boosts-learning

The University of Arizona. (2019, July 24). L2L Strategy – Interleaving. Academic Affairs. https://academicaffairs.arizona.edu/l2l-strategy-interleaving