How does "Spaced practice" work?

Letting some forgetting happen between study sessions makes the next retrieval more effortful, and that effort is exactly what strengthens the memory — re-learning something you have partly forgotten builds a more durable trace than restudying something still fresh. Massed practice feels efficient because everything stays fluent, but that fluency fades fast after you stop.

How does "Interleaving" work?

Practicing one type of problem in a long block lets you reuse the same approach mechanically without choosing it, so you never learn which strategy fits which situation. Interleaving forces you to discriminate between problem types and retrieve the right approach each time, which is the skill you actually need when problems arrive unsorted in the real world.

How does "Elaboration" work?

Elaboration — restating an idea and tying it to existing knowledge — builds more retrieval paths to the new material, making it both better understood and easier to recall. Connecting new ideas to prior knowledge gives them a structure to attach to rather than floating in isolation. The richer the connections, the more durable and usable the memory.

How does "Generation: attempt before you are taught" work?

Attempting an answer before being given it primes the mind to absorb the correct answer more deeply, because the struggle creates a gap the explanation then fills. Even unsuccessful attempts improve later learning, since they activate related knowledge and make you notice exactly what you were missing. Errors made in the attempt, when corrected, become learning rather than failure.

How does "Beware illusions of knowing" work?

Rereading and massed practice create a sense of familiarity that the mind misreads as mastery, producing confident learners who fail the test. Because the techniques that feel easiest are often the least effective, your subjective sense of learning is an unreliable guide. The fix is to calibrate against objective performance — testing reveals what fluency conceals.

Brown, Roediger & McDaniel ("Make It Stick")

What does "Make It Stick" say are the most effective ways to learn?

Retrieval, spacing, interleaving, and elaboration — the evidence-backed core

Short answer

"Make It Stick", by Peter Brown with psychologists Henry Roediger and Mark McDaniel, distills decades of cognitive science into a few high-leverage practices: retrieval practice, spacing, interleaving, and elaboration. Its central counterintuitive claim — that the most effective learning feels harder and slower than rereading — is backed by strong experimental evidence.

The book’s core message is that our instincts about learning are mostly wrong: the techniques that feel productive (rereading, massed practice) are weak, and the ones that feel effortful and frustrating are the ones that last. These "desirable difficulties" are among the best-supported findings in cognitive psychology. Below are the core practices, each with the mechanism that makes it work and an honest read on the evidence.

The practices (6)

Why it works

Pulling information out of memory strengthens it far more than putting it back in by rereading, because retrieval reconsolidates and reinforces the memory trace and makes it easier to access later. Each successful effortful recall is itself a powerful learning event, not merely a measurement. This is why testing should be a study tool, not only an assessment.

How to do it

1After studying, close the material and write down everything you can recall.
2Use flashcards or practice questions that force production, not recognition.
3Test before you feel ready; the difficulty is where the benefit comes from.

Evidence

RCT / meta-analysis

The testing effect is one of the most replicated findings in cognitive psychology: across many controlled experiments and meta-analyses, retrieval practice produces substantially better long-term retention than restudying the same material.

Honest caveat: Retrieval helps most when it is effortful but mostly successful; with material that is far too hard, some initial study or hints are needed before testing pays off.

— Roediger & Karpicke (2006), "Test-Enhanced Learning", Psychological Science

Common mistake: Rereading and highlighting because it produces a comforting sense of fluency, then mistaking that recognition for the ability to recall the material when it counts.

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