Interleaving vs. Blocked Practice: Which Wins for Long-Term Learning? | Chapterly Blog
Interleaving vs. Blocked Practice: Which Wins for Long-Term Learning? Quick Answer: Interleaving is mixing different topics or problem types within a single study session. Blocked practice is grinding one topic at a time before moving on. Blocked practice produces faster short-term gains and feels more productive. Interleaving feels harder and produces slower in-session gains, but typically produces 20-40% better retention and transfer on a delayed test a week or month later. The advantage only appears when the mixed topics are genuinely confusable; mixing unrelated material produces little benefit. The practical rule for a reader or self-learner is to block while first encountering a topic, then switch to interleaving once basic execution is fluent. Most studying looks like this. You open the textbook, read chapter four, do the chapter-four problems, move on to chapter five, do the chapter-five problems. One topic at a time. It feels orderly, it feels efficient, and it produces a pleasing sense of mastery as each chapter's exercises start to come quickly. That feeling is partly an illusion. Forty years of cognitive-psychology research keeps finding the same uncomfortable result: the studying that feels most efficient in the moment is often the studying that produces the worst long-term...