Josh was in second grade. He couldn’t read the books his mom checked out from the library. In addition, he couldn’t read 1st grade phonics books. Josh’s mom was stunned, as she didn’t realize he was so behind. Once Josh’s mom looked deeper into her son’s phonics lessons, she realized his lessons were missing something. He brought home lists like the following: ten, men, red, bed, wed. His lists did not contain interleaving.
She thought the school was using research-based instruction. However, she hadn’t heard of interleaving. The more she dug, the more she learned that the school was not in line with the research at all. Interleaving is often missing from phonics lessons. If you want to improve your students decoding skills, interleaving is one of the most effective strategies you can use.
Many parents assume their child is learning phonics. Yet, if the program lacks interleaving, many, many kids will struggle. If your student comes home with phonics materials and books, but still struggles, this post is for you.
Many teachers have discovered the power of interleaving already. Teachers who use interleaving allow their students to learn faster and retain learning longer. Without interleaving, many students, especially struggling readers, forget rapidly.
This post outlines:
- what interleaving is
- its incredible effectiveness in teaching decoding skills
- how to identify phonics lessons that use interleaving
What is interleaving?
Interleaving essentially means mixed practice. While a lot of people are familiar with blocking, wherein kids practice one skill at a time, few are familiar with interleaving. Blocking implies kids learn skill A before skill B. For example, a basketball player might learn to shoot a free throw (skill A) before he learns to shoot a 3-pointer (skill B). In blocking, practice looks like: AAABBB.
In interleaving, these skills are mixed once skill B is introduced. For example, a basketball player might shoot a free throw, then a 3-pointer and then a free throw, then a 3-pointer…etc. In interleaving, practice looks like: AABABABBA. Practice is mixed.
Interleaving samples
Let’s use another example. Say you’re trying to learn world capitals. In blocking, you’d do the following:
What is the capital of Columbia? Bogota
What is the capital of Columbia? Bogota
What is the capital of Columbia? Bogota
What is the capital of Nigeria? Abuja
What is the capital of Nigeria? Abuja
What is the capital of Nigeria? Abuja
What is the capital of Switzerland? Bern
What is the capital of Switzerland? Bern
What is the capital of Switzerland? Bern
What is the capital of Angola? Luanda
What is the capital of Angola? Luanda
What is the capital of Angola? Luanda
As you can see, the concepts are blocked together.
In interleaving, learning world capitals would look like the following:
What is the capital of Columbia? Bogota
What is the capital of Nigeria? Abuja
What is the capital of Columbia? Bogota
What is the capital of Switzerland? Bern
What is the capital of Nigeria? Abuja
What is the capital of Columbia? Bogota
What is the capital of Switzerland? Bern
What is the capital of Angola? Luanda
What is the capital of Switzerland? Bern
What is the capital of Columbia? Bogota
What is the capital of Nigeria? Abuja
What is the capital of Angola? Luanda
Concepts are still introduced slowly. Notice, “What is the capital of Angola?” is not introduced until question 8. In addition, old material is mixed with new material.
Interleaving is incredibly powerful. If you follow interleaving study strategies you’re a lot more likely to remember the information you’ve studied. In addition, you’re a lot more likely to access the information when you need it.
Interleaving in phonics lessons
Many phonics lessons follow blocking, but fail to use interleaving. Blocking and interleaving are not mutually exclusive. They can and should occur together. For example, a student learns short a, then short i, and then they practice both together: fit, cap, mitt, Sam, nap, rip…etc.
Usually, phonics lessons (unfortunately) only use blocking. In essence, educators provide wordlists with all one sound unit: fear, speak, bean, gear, mean…etc. Then, they abandon the phonics sound and move on to another phonics sound. The new phonics lessons contain all one phonics sound again: fair, sail, rail, rain, pain, mail.
In reading lessons, interleaving looks more like the following: fear, spike, deer, net, dear, hop, hand, fret, seal. In this second sample, students get to practice old and new phonics sounds together. This is a mixed list. When a new phonics sound is introduced, the mixed practice will continue: fair, tear, sail, tan, pile, fond, main, band…etc.
Benefits of Interleaving
To convince you of the benefits of interleaving, let’s look outside the field of reading. Medical students who learned with interleaving produced a more accurate electrocardiogram diagnoses. Basketball players who use interleaving make more accurate shots. Art students are better able to look at a painting and identify the artist if they’ve used interleaved practice.
In nearly every area, if we use interleaving, we retain information better. This is especially critical for children learning to read. Many kids forget phonics sounds because they haven’t received interleaved practice.
What’s the deal? Why do few phonics lessons use interleaving?
Interleaving or mixed practice is extremely powerful. It is one of the most effective learning strategies. Unfortunately, researchers did not know of its power until 1987. Many reading programs, even dyslexia reading programs, were created before the positive effects of interleaving were known. Thus, they do not contain interleaving.
For many educators, it is tempting to abandon interleaving. After all, blocking is easier. If you repeat the same concept over and over and over without spacing or anything else in between, of course our students will get it right! Blocking gives us the illusion that our students are retaining information.
Yet, once other concepts are introduced, without interleaving, old concepts are often forgotten. Interleaving is harder, and students make more mistakes in the short-term. However, in the long-term, the payoff is profound and undeniable. With interleaving, students retain information.
Reading Elephant books use interleaving
It’s unfortunate that many reading programs choose between either blocking or interleaving. They should be used together. Of course we teach skill A before skill B. However, once skill A and skill B have been introduced, we must mix them. 
Teachers are often stuck with phonics lessons that have chosen between blocking or interleaving. This is a real problem. It is the core reason why so many kids struggle with learning how to read. While phonics is essential, it’s simply not enough. We must follow the learning science too. Blocking and interleaving both have profound, positive effects. Don’t pick one. Use both.
Reading Elephant books use both blocking and interleaving. Our books introduce one phonics sound at a time (blocking). In addition, the books weave old phonics sounds into new books (interleaving). In this way, kids get the chance to practice old material.
Let’s spread the word about the powerful effects of interleaving!
References:
Brown, Peter C., Roediger 111, Henry L., McDaniel, Mark, A. (2014) Make it Stick: The Science of Successful Learning.
Pan, Steven C. (2015) The Interleaving Effect: Mixing it Up Boosts Learning. Scientific American. https://www.scientificamerican.com/article/the-interleaving-effect-mixing-it-up-boosts-learning/
Such a useful article. I couldn’t agree more – building on past experience is far superior than the marching constantly forward.
Yes, if we march forward constantly, kids forget. We adults also forget things if we don’t review them! Thank you for your interest in interleaving Clare!