Change It Up!: Interleaved Practice–What It Is, Why It Works
What is Interleaved Practice?
Repetition is the most time-honored method of learning anything new, be it basketball, math, or piano. Practice! And practice some more.
But how do we structure practicing? How musicians or math students organize their practice and study time is not frequently discussed or thought about in great detail. Music students routinely leave their lessons with a list of items to work on, but teachers rarely advise how they might best allocate their practice minutes each day.
Intuitively, we tend to work on improving one skill at a time, usually with much repetition, until gains are made. In psychology research, this is termed blocked practice, defined by working on a specific task, fixing it through repetition-focused practice, and then moving to a new skill.1 There is an impression of fluency gained and improvement made, with a sense of bringing something to closure at the end of each practice segment. Blocked practice can be illustrated as: AAABBBCCC.
But performers often return to the practice room the next day to find that the skills learned yesterday with much repetition, did not stick. The improvement from blocked practice wasn't retained over a longer period of time.
Another, more effective approach shown in the research, is interleaved practice. In this method, a student practices an identified problem area for a brief amount of time, leaving it to begin practicing a different skill area. The performer is alternating and intermixing the practice tasks. The long-term retention is better with interleaved practice, even though the short-term satisfaction isn't as great. Interleaved practice can be illustrated as: ABCBACACB.
Research into how we best learn has been accumulating for more than four decades, substantiating that interleaved practice is much more effective than blocked practice in many domains—from sports, to math, to much classroom learning.2 While the research in music has been less, it also confirms that interleaved practice is effective for efficient learning.
Research on Interleaved Practice in Music
Christine Carter and Jessica Grahn conducted a research study with advanced clarinetists, dividing them into either blocked or interleaved groups. The performers were given an exposition of two concertos and a technical etude to practice. While the practice time was the same for each group, the interleaved group practiced the concertos in four short, threeminute practice sessions versus one twelve-minute session for the blocked practice group.3
At the conclusion of their practice, the students performed the excerpts for evaluation by outside adjudicators. They also returned day two and performed the same material again for evaluation.
Most importantly, the interleaved practice schedule produced greater improvement in the student performances when evaluated the second day. While blocked practice did show higher evaluation scores immediately after practicing, interleaved practice produced better, longer-lasting results.
Why Is Interleaved Practice More Effective than Blocked Practice?
Researchers believe that every time the brain is forced to restart the learning of new material, as in interleaved practice, more long-term retention takes place. Continually repeating an action, as in blocked practice, requires less brain attention, reducing the possibility of longer-term learning. It's the more effortful work required of the brain when alternating tasks that produces better results.4
Why Isn't Everyone Using Interleaved Practice?
Why isn't every student practicing in this way if it's so effective? Going back to the research study with the clarinetists, we see a surprising answer. While the majority of participants acknowledged that interleaved practice was more useful, they preferred blocked practice. Several other studies have found the same results, with participants performing better on tasks after interleaved practice, but still favoring blocked practice.5 Researchers acknowledge that repetition during blocked practice produces a sense of fluency and improvement, but it doesn't necessarily mean that material has been retained. The facility gained during frequent repetition is highly motivating, and thus can easily be preferred, even though it may not be remembered over a long period of time. The authors of the popular book on learning, Make It Stick, comment:
As we practice a thing over and over we often see our performance improving, which serves as a powerful reinforcement of this strategy. We fail to see that the gains made during repetitive practice come from short-term memory and quickly fade. Our failure to perceive how quickly the gains fade leaves us with the impression that massed (blocked) practice is productive.6
Interleaved practice frequently feels unnatural, as if the learning process is being interrupted. Certainly, it requires planning and greater focus. The student has to trust that long-term learning is taking place when using interleaved practice.
How to Implement Interleaved Practice
It's important for both students and teachers to remember: blocked practice feels more intuitive, interleaved practice feels less intuitive, more effortful. Given this phenomenon, what teaching strategies can teachers use to help students implement interleaved practice?
Technical drill work, or any practice task that feels tedious, such as learning notes, establishing fingering, or memorizing, can benefit from interleaved practice. Using a timer, such as found on cell phones, can be critical to combat the non-intuitive aspect of having to stop just as one is "getting" a passage. It's helpful to experiment with five-, seven-, or ten-minute intervals, finding what best suits a particular task. Advanced students may prefer to alternate fifteen- or twenty-minute sessions.
Elementary students will benefit if a teacher initially suggests an interleaved practice plan that includes what books, pieces, or exercises can be alternated in practice. Rotating elements two, three, or four times is most beneficial for students.
For elementary and intermediate students, interspersing technical practice such as scales, cadences, and arpeggios, between repertoire work can ensure that any less-fun elements are easily accomplished. Likewise, any persistent technical problem, memory glitch, or fingering change will be solved more quickly if practiced several times, intermittently, during each practice session.
Advanced students find they must plan ahead to decide what passages or sections in works will be interspersed in practice. Already this eliminates the usual "start at the beginning and play until there's a mistake, stop and fix each random mistake" that is frequently the center of much practicing. Teachers suggesting specific passages or technical exercises that would benefit from interleaved practice will help students begin incorporating an alternating approach to practice.
After students have used interleaved practicing successfully, they will find it helpful when they must suddenly learn new music or incorporate a new technique. Teachers frequently suggesting specific skills or passages that would benefit from interleaved work will keep the concept of alternating tasks in the forefront of students' practicing arsenal.
Interleaved practice also offers significant benefits to help offset the stress of live performances that offer no chance of starting over, as one does in repetitive practice. The act of daily practicing challenging sections with an alternating strategy builds confidence that technical difficulties will hold up through the inevitable distractions during recitals.
Teachers that implement the principles of interleaved practice, by rotating activities, will find their pacing improves and students are more engaged. In group piano classes, interspersing technical skill items such as scales and cadences two or three times during a fifty-minute class period for one-two minute drills, can be far more effective than one longer six- to ten-minute practice session. This easily avoids the glazed-eye syndrome during technique work.
Cycling back several times to a repertoire piece, both in group and private lessons, can have numerous benefits for students. New skills the teacher is advocating are more easily reinforced with several short trials, rather than one long practice session. Checking memory, by a quick return to a particularly vexing section, can test if the passage is holding up in the moment. This becomes an automatic confidence booster for students.7
While historically a typical response to becoming more accomplished at the piano was to practice a skill over and over until it was better, the current research shows that our brains may prefer, and our performances will improve, when we switch between practice tasks. Returning to material several times within one work session will produce longer-lasting learning for musicians. Rather than the old adage, Practice Makes Perfect, we can now add Change It Up!—helping practice become more reliable and efficient.
1. The research literature sometimes refers to block practice as massed practice.
2. See the article by Kelli Taylor and Doug Rohrer for an overview of research on interleaved practice in many domains: "The Effects of Interleaved Practice," Applied Cognitive Psychology. Vol. 24, no. 6, (September 2010): 837-848. doi: 10.1002/acp.1598.
3. Researchers Christine Carter and Jessica Grahn asked ten clarinetists to practice expositions from Stamitz Concertos in F Major and E-Flat Major and two exercises from Jean-Xavier Lefevre's Methode de clarinette. See their full research study: "Optimizing Music Learning: Exploring How Blocked and Interleaved Practice Schedules Affect Performance." Frontiers of Psychology. Vol. 7, article 1251, (August 2016): 1-10. https://www.frontiersin.org/articles/10.3389/ fpsyg.2016.01251/full
4. For an understandable discussion of the science behind learning efficiently, see Peter Brown, Henry Roediger, and Mark McDaniel's book Make it Stick, in addition to Benedict Carey's book How We Learn. Both discuss the importance of interleaved practice, sometimes also called distributed practice, over time.
5. Researchers Nate Kornell and Robert Bjork discuss the phenomenon of preferring massed practice, even knowing that it's less effective, at length in their research study "Learning Concepts and Categories: Is Spacing the Enemy of Induction?" Psychological Science. Vol. 19, no. 6, (June 2008): 585-592. https://www.ncbi.nlm.nih.gov/ pubmed/18578849.
6. Peter Brown, Henry Roediger, and Mark McDaniel, Make It Stick: The Science of Successful Learning (Cambridge, Massachusetts: The Belknap Press of Harvard University Press, 2014), 204.
7. Authors Jennifer Mishra and Barbara Fast discuss interleaved practice and interleaved teaching in their book, iPractice: Technology in the 21st Century Music Practice Room (New York: Oxford University Press, 2019), 8-11.