Does your child study Maths for two hours straight before moving on to Reading? While focusing on one subject at a time feels logical, cognitive science proves it is highly inefficient. Drawing on the research from Make It Stick: The Science of Successful Learning, this article reveals why a counterintuitive strategy called “interleaving” — mixing different subjects in a single study session — builds the mental agility Australian students need to excel in the Selective Test, OC test, and NAPLAN.
When Australian parents help their children prepare for the Selective High School Placement Test, Opportunity Class (OC) test, NAPLAN, or scholarship exams, they often encourage a highly focused approach. A typical study session might involve spending an hour solely on mathematics, followed by an hour entirely dedicated to reading comprehension.
This method, known as “blocked practice,” feels logical and efficient. However, cognitive science reveals a surprising truth: it is not the most effective way to learn.
In their groundbreaking book, Make It Stick: The Science of Successful Learning, cognitive scientists Henry L. Roediger III and Mark A. McDaniel, along with writer Peter C. Brown, introduce a counterintuitive but highly powerful study strategy: interleaving.
Interleaving involves mixing different subjects, problem types, or skills within a single study session, rather than focusing on one topic at a time. While it initially feels more difficult and less productive than blocked practice, the research is clear: interleaving produces superior long-term learning and significantly higher test scores.
To understand why interleaving works, we must first look at the flaws of blocked practice. When a student spends an hour solving 20 identical math problems—for example, calculating the area of a triangle—they quickly learn the formula. By the fifth problem, they no longer need to think about which formula to use; they simply plug in the numbers.
This repetition creates a strong sense of fluency. The student feels they have mastered the concept. However, as the authors of Make It Stick explain, this is often an “illusion of knowing.” The student has learned how to execute the formula, but they have not learned the crucial skill of identifying when to use it.
When exam day arrives, the problems are not neatly grouped by topic. A question about the area of a triangle might be followed immediately by a question about fractions, and then a question requiring logical deduction. The student, accustomed to blocked practice, suddenly struggles. They know the formulas, but they cannot determine which one applies to the specific problem in front of them.
Interleaving solves this problem by simulating the unpredictable nature of a real exam. Instead of doing 20 area problems in a row, an interleaved study session might mix five area problems, five fraction problems, five geometry problems, and five logic puzzles.
This approach forces the brain to work much harder. The student cannot simply apply the same formula repeatedly. For every single question, they must first analyse the problem, determine the underlying concept, and then select the appropriate strategy.
This continuous process of discrimination and selection is what makes interleaving so powerful. As the authors of Make It Stick note, “When practice is spaced, interleaved, and varied, it requires more effort. You feel the increased effort, but the learning is deeper and more durable.”
For Australian students preparing for the Selective Test or OC test, the ability to quickly switch gears between different types of problems is essential. These exams are designed to test not just rote knowledge, but cognitive agility and problem-solving skills under time pressure.
Interleaving trains the brain to become highly adaptable. It teaches students to recognize the subtle differences between similar-looking problems and to rapidly retrieve the correct solution strategy from their long-term memory.
While interleaving feels slower and more frustrating in the short term, it builds the robust, flexible knowledge required for high-stakes exams. It is a “desirable difficulty” that transforms fragile familiarity into genuine mastery.
For parents, implementing interleaving can be as simple as changing how study sessions are structured:
At TestMagic, our online practice platform naturally facilitates interleaving. Our realistic practice tests for the Selective Test, OC test, and NAPLAN present questions in a mixed format, exactly as they appear in the actual exams. By regularly completing these mixed practice papers, students are forced to constantly discriminate between problem types and select the correct strategies.
This consistent, effortful practice is the key to building the mental agility required for exam success. By embracing the science of interleaving, you can help your child study smarter and score higher.
To discover more evidence-based strategies for exam preparation, read our final article in this series: How to Help Your Child Study Smarter, Not Harder. For further insights into the benefits of physical activity on cognitive function, see How Sport Improves Your Child’s School Results.
