Interleaving Practice: Why Mixing Problem Types Can Help
Reviewed byMedical & Pedagogical Advisory Team
Disclaimer: This article is for educational purposes based on peer-reviewed research and does not replace professional medical or diagnostic advice.
Students often practise one problem type repeatedly before moving on. Interleaving mixes related problem types so learners practise choosing the right method, not only repeating a familiar procedure.
What the research says
Interleaving can help learners distinguish between related problem types and decide which method to use. It is most useful when the problems are meaningfully related; mixing completely unrelated subjects has not been established in the same way.
How to do it, step by step
Blocked practice means ten problems of type A, then ten of type B. Interleaved practice mixes A, B and C in one set, so each problem starts with the question: which method fits here?
In maths, mix area, perimeter and volume. In languages, mix past and present tense sentences. In science, mix questions about related processes. If a learner is brand new to a method, practise it alone first.
Practical checklist
✓ Two or three related problem types chosen
✓ Problems shuffled, not grouped
✓ Learner names the method before solving
✓ Blocked practice used only for first introduction
Evidence & sources
Peer-reviewed research this article is based on.
Teaching the Science of Learning
Yana Weinstein, Christopher R. Madan, Megan A. Sumeracki · Cognitive Research: Principles and Implications · 2018