The best study techniques are practice testing (recalling information from memory) and distributed practice (spreading your study over days and weeks). Techniques like interleaving and self-explanation help in many situations, while highlighting, passive rereading and passive summarising do much less than they feel like they do.
That ranking follows the most widely cited review of the topic, Dunlosky and colleagues (2013), which examined ten common learning techniques and judged how useful each is across different learners, materials and tasks. This article translates that review into plain tiers and then shows how to combine the good ones into a routine you can actually follow.
How the techniques are ranked
Dunlosky et al. did not ask which method feels best. They asked how consistently each technique improved learning across many experiments, for different kinds of students and content. The results here are described qualitatively, because the exact size of an effect depends on the study, the material and the test.
A caution: the tiers describe typical usefulness, not a law. A “low” technique can still have a niche use, and any technique done badly will underperform.
High utility: use these as your foundation
Practice testing
Practice testing means pulling information out of your head instead of putting it back in: flashcards, past papers, self-quizzing, writing down everything you remember from a chapter before checking. In many experiments, students who tested themselves remembered more later than students who spent the same time rereading, an effect often called the testing effect (Roediger & Karpicke, 2006 is the classic demonstration).
Why it works: retrieval is effortful, and effort strengthens the memory. It also shows you what you do not know, which rereading hides. More on this in active recall versus rereading.
Distributed practice
Distributed practice, also called spacing, means splitting study into shorter sessions over time instead of cramming. Reviews of the research, including Cepeda and colleagues (2006), found that spreading practice generally leads to better long-term retention than massing it, and the gap matters most when you need to remember something for weeks or months.
It pairs naturally with testing: test yourself, leave a gap, test again. That combination is what spaced repetition automates. The background is in our forgetting curve explainer.
Moderate utility: worth using in the right places
Interleaving
Interleaving mixes different problem types or topics within a session instead of finishing one block before starting the next. Research by Rohrer, Taylor and others suggests it helps most when you must choose which method to apply, for example in maths or physics problem sets. It feels harder and slower while you do it, which is part of why people avoid it.
Elaborative interrogation
This means asking yourself “why is this true?” and “why does this make sense?” about a fact, then answering from what you know. It works best when you already have some background knowledge to connect the new fact to. Early in a topic, you may not have enough to explain with.
Self-explanation
Self-explanation means describing, in your own words, how you got to a step or how an idea connects to what you already know. It is especially good for worked problems: explain each step and why it is valid.
The Feynman technique is a popular form of this. You pick a concept, explain it as if to a beginner, notice where your explanation breaks down or leans on jargon, go back to the source to fix those gaps, then explain it again. It is a named method rather than a formal research programme, but it does what self-explanation does: it exposes the difference between recognising an idea and being able to produce it.
Low utility: fine as a helper, poor as a plan
Highlighting and underlining
Highlighting feels productive because you are doing something with the text. The problem is that it rarely forces retrieval or deeper processing, and it is easy to highlight far too much. Dunlosky et al. rated it low utility when used as the main method.
Practical use: highlight lightly on a first read as a way to mark material, then turn those marks into questions.
Rereading
Rereading is the default for many students. It builds familiarity, and familiarity produces the illusion of knowing: the page looks familiar, so you assume you could reproduce it. It can help a little, especially for a first pass, but it loses to testing on the same time budget.
Summarising done passively
Summarising can work if you write from memory and then check. Copying or paraphrasing while looking at the text mostly rehearses the wording. The review rated summarising as low utility partly because its benefit depends heavily on how well people do it.
Keyword mnemonics and imagery
The keyword method, where you link a new word to a vivid image via a similar-sounding word, can work for specific kinds of material such as foreign vocabulary. The catch is that it does not generalise well to abstract concepts and often fades. It is situational rather than a core method.
Quick reference table
| Tier | Technique | Best use |
|---|---|---|
| High | Practice testing | Everything you need to remember or apply |
| High | Distributed practice | Anything needed beyond the next few days |
| Moderate | Interleaving | Problem-solving subjects |
| Moderate | Elaborative interrogation | Facts you can connect to prior knowledge |
| Moderate | Self-explanation (incl. Feynman) | Concepts and worked problems |
| Low | Highlighting | Light first-pass marking only |
| Low | Rereading | A single initial read |
| Low | Passive summarising | Only if done from memory |
| Situational | Keyword mnemonics | Vocabulary and arbitrary pairings |
A weekly routine that combines them
You do not need all ten. This routine uses the top of the list and fits a few short sessions a week.
- Day 1, learn it. Read or watch the material once. Mark lightly. Then close it and write down everything you remember, and check what you missed.
- Day 1, make questions. Turn the important points into questions or flashcards. Our guide to making good flashcards covers how.
- Days 2, 4 and 6, short retrieval sessions (15 to 20 minutes). Test yourself on new and older material. Mix topics within the session (interleaving).
- Once a week, explain it. Pick the two or three hardest ideas and do a Feynman-style explanation out loud. Fix whatever you stumble on.
- Weekly review of misses. Anything you keep getting wrong goes back into the next week’s rotation.
- Before an exam, do timed practice. Full past papers or mock exams under realistic conditions.
If time is tight, keep just two habits: test yourself, and do it again a few days later.
Where tools fit
Spacing is the part people find hardest to manage by hand, which is why many students use a scheduler. Lernoa’s flashcards use an SM-2-style spaced-repetition scheduler with Again, Hard, Good and Easy ratings, and it is free to use without limit. Anki does similar work, and a paper Leitner box does too if you prefer analogue. The tool matters far less than doing the retrieval and spacing it consistently.
Try it
Pick one subject this week and replace one rereading session with a self-test. Write ten questions from memory, answer them without looking, and check. If you want the scheduling handled for you, you can start free and build a deck of your own, or read the study guide first.
Frequently asked questions
What is the most effective study technique?
Practice testing, meaning trying to recall information from memory rather than looking at it, is the most consistently supported technique. Spreading that practice over days and weeks makes it work even better.
Is highlighting a good way to study?
On its own it is one of the weaker methods, because it feels productive without requiring you to recall anything. It is fine as a first pass to mark what you will later turn into questions.
Is rereading notes useless?
Not useless, but it is a poor use of limited time compared with testing yourself. It builds familiarity, and familiarity is easy to mistake for knowing.
Is the Feynman technique backed by research?
The Feynman technique is a named method rather than a formal study, but it is a form of self-explanation, which research on learning supports. Explaining an idea simply and noticing where you get stuck exposes gaps effectively.