Unraveling the Art of Interleaving: A Key Strategy for Improved Learning
“What is this?” you might be asking. Put simply, interleaving is a learning strategy that involves taking ideas or concepts you are trying to learn and mixing them up. For interleaving to be most effective the concepts should be related; they should all be within one subject. Interleaving breaks students out of ineffective practice habits that may only have short-term benefits. We’re working with our students to build durable results. This strategy also has the added benefit of giving students new perspectives on a variety of problem-solving approaches. It also shows our students how they can mix up their practice strategies so that they’re not stuck with a single strategy that might not work.
Let’s begin with three common occurrences:
1. Asking a student to start playing at any point in a piece other than the beginning, only to have them tell you they need to start at the beginning to get there.
2. Experiencing memory slips (either your student or yourself) in the middles of pieces, while beginnings and endings are crystal clear.
3. A student is confusing a phrase in one section with a similar phrase from a previous section.
Why do I bring these up? And what can we do about these issues?
There are a quite a few reasons:
1. Students often want to start phrases, sections, or entire pieces over if they play a wrong note or have a memory slip. Interleaving is a great strategy for alleviating this counterproductive habit. Don’t just teach repertoire linearly; pieces of music are like pieces of a puzzle that fit together in a certain order to complete the whole but can be taken apart and viewed on their own. Interleaving involves mixing things up to promote long-term retention. Another way to think about interleaving is just rearrangement of retrieval opportunities (more on retrieval practice in another post).
2. Much of our work in the practice room is blocked: practicing one thing repeatedly until it feels a little more comfortable than it did when we started, then moving on to the next thing. But this approach doesn’t allow students to think about what practice strategies might be most effective. It also narrows the amount of retrieval cues available for a given piece or passage, weakening our ability to retrieve information as we progress through a piece or through a recital program.
3. When things are interleaved, students must choose an appropriate practice strategy, not just use a one-size-fits-all strategy that might not be as effective (Agarwal & Bain, 2019). (For more on specific practice strategies see Part Two of Practicing for Artistic Success by Burton Kaplan)
Interleaving for musicians and music students can take a variety of forms:
Interleaving between pieces: switching from one piece to another
Typical student practice is blocked. One piece is practiced before moving on and likely looks like this:
Piece 1: 30 minutes | Piece 2: 30 minutes | Piece 3: 30 minutes | Piece 4: 30 minutes |
Interleaving pieces while still utilizing the same amount of practice time might look more like this:
Piece 1: 10 mins | Piece 2: 10 mins | Piece 4: 10 mins | Piece 3: 10 mins | Piece 2: 10 mins | Piece 4: 10 mins | Piece 1: 10 mins | Piece 3: 10 mins | Piece 2: 10 mins | Piece 4: 10 mins | Piece 1: 10 mins | Piece 3: 10 mins |
Dividing the 30 total minutes spent on each piece into 10-minute chunks with other repertoire practiced in between helps promote problem-solving by making students decide the best practice approach for specific passages over a more focused amount of time.
2. Interleaving within a piece: mixing phrases and section
A single piece can be interleaved. For example, a piece in ternary form – containing an A section, a contrasting B section, and an A’ section – when practice is blocked (which is often the case) would likely be one section practiced repeatedly, then the next section in the same fashion, and the last section blocked as well:
AAA BBB A’A’A’
That same piece when practice is spaced (or distributed) each section is practiced the same number of times, but in serialized positions. And each section here is spaced out by the other, intervening sections:
ABA’ ABA’ ABA’
That same piece, when practice is interleaved, would look very different. There are still the same number of repetitions, but the order is a bit more mixed:
B A’ B A A’ A B A’ A
Interleaving, such as this previous example, promotes differentiation. Students learn to detect subtle similarities and differences. In a 2008 study by Bjork and Kornell, participants were asked to identify various painters by studying their painting styles. On subsequent identification tests, the group that interleaved their study of paintings by different artists outperformed the group that blocked their study of paintings by individual artists together (Bjork & Kornell, 2008). This type of differentiation – detecting subtle differences and similarities – is important when learning pieces that contain parallel periods, or when you come across similar passages which appear in slightly altered forms in different sections of a piece.
3. Interleaving across practice sessions
This first infographic represents a student’s typical practice day (although the amount of to-be-practiced material will vary depending on each student; I based it on the practice routines of some of my older students). This hypothetical student has four pieces, two exercises, and two etudes – each with three practice points – to work on. They’d start at the top of the big circle (practice item #1) and practice the three points in clockwise order, then move clockwise to the next item.
The second infographic shows all practice components interleaved in their second practice session during the same day (side note: two separate practice sessions in one day is a form of spaced practice). They’d still start at the top of the big circle and work their way clockwise through each item but notice the practice items are reordered. They’d also still work clockwise through the practice points, but these are also reordered.
We have to recognize that interleaving isn’t something all students can just jump into. Some students may need “scaffolding,” or a mix of blocking and interleaving (Agarwal & Bain, 2019). It’s also important to note the differences between spacing and interleaving: spacing is spreading things out over time, with the time in between filled with unrelated activities; interleaving is how things are mixed up, and any intervening time is filled with related activities (Agarwal & Bain, 2019).
References
Agarwal, P. K., & Bain, P. M. (2019). Powerful Learning: Unleash the Science of Learning. San Francisco: Jossey-Bass.
Bjork, R. A., & Kornell, N. (2008, June). Learning Concepts and Categories: Is Spacing the "Enemy of Induction"? Psychological Science, Vol. 19, No. 6, pp. 585-592.
Rohrer, D. (2012, September). Interleaving Helps Students Distinguish among Similar Concepts. Educational Psychology Review, Vol. 24, No. 3, pp. 355-367.
Rohrer, D., Dedrick, R. F., & Agarwal, P. K. (2017). Interleaved Mathematics Practice: Giving Students a Chance to Learn What They Need to Know. Retrieved from retrievalpractice.org: https://www.retrievalpractice.org/strategies/2019/4/3/interleaving
