Best revision techniques, ranked by the evidence
In short
The revision techniques with the strongest evidence are practice testing — flashcards, blurting, past questions, anything that makes you answer from memory — and distributed practice, which means spreading the same work across days and weeks. Interleaving, elaborative interrogation and self-explanation have moderate support. Highlighting, re-reading, summarising and keyword mnemonics, the techniques most students spend most of their time on, rate low. The ranking comes from Dunlosky and colleagues' 2013 review of ten learning techniques, and it has held up.
The ranking
In 2013, Dunlosky and colleagues reviewed the evidence for ten common learning techniques and rated each on how well it works across different students, materials and kinds of test. Two came out high, three moderate, five low. Here is the ranking, translated into what each technique looks like for a GCSE student.
| Technique | Rating | What it looks like at GCSE | The common mistake |
|---|---|---|---|
| Practice testing | High | Flashcards, blurting, past questions, end-of-topic quizzes, teaching it back | Flipping cards without answering; testing only what you already know |
| Distributed practice | High | Revisiting each topic at 1, 3, 7, 14 and 30 days; short daily sessions | Cramming; a timetable that visits each topic once |
| Interleaving | Moderate | Mixing question types and subjects within a session | Thirty of the same question in a row; mixing before the basics are secure |
| Elaborative interrogation | Moderate | Asking "why is that true?" of a fact and answering from memory | Accepting "because it is"; answering with the book open |
| Self-explanation | Moderate | Explaining each step of a worked example or process in your own words | Reading the worked example and nodding |
| Summarising | Low | Condensing notes onto one page | Copying the notes with fewer words; never testing from the summary |
| Highlighting | Low | Marking key terms in text | Highlighting most of the page; counting it as a revision session |
| Keyword mnemonic | Low | An image linking a new word to a familiar one, mostly for vocabulary | Using it for things that need understanding, not recall |
| Imagery for text | Low | Picturing what a passage describes as you read | Works only for concrete, descriptive material |
| Re-reading | Low | Reading the notes or textbook again | The default for most students; mistaking familiarity for knowledge |
Two cautions. "Low" does not mean useless: highlighting and summarising are reasonable ways to prepare material for testing, and poor ways to spend the third hour on a topic. And "moderate" often means less studied rather than less effective — interleaving in particular has gathered more support since 2013, especially in maths.
High utility: practice testing
Practice testing means retrieving the answer from memory before you check it. It has the strongest evidence of any technique on the list, and it takes many forms.
At GCSE it looks like flashcards answered before you flip, a blank page filled from memory, end-of-topic questions with the book shut, past-paper questions under time, and explaining a topic aloud to someone who will notice when you stall. The mechanism — and why it feels worse than re-reading while working better — is in active recall vs re-reading. The two most practical forms have their own guides: how to make flashcards that work and the blurting method.
How students get it wrong: testing that is not really testing. Flipping a card and thinking "yes, I knew that". Doing the quiz with the notes open. Testing only the topics that feel good. The check is whether you found something you did not know; if you never do, you are not testing.
High utility: distributed practice
Distributed practice means spreading the same study time over several sessions with gaps between them. It is the other technique rated high, and it makes every other technique work better.
For a GCSE student it means a topic revisited on day 1, day 3, day 7, day 14 and day 30 rather than for two hours once. The spacing effect is among the most replicated findings in the study of memory, and it holds for facts, skills and essays alike; the schedule and the reasons students abandon it are in spaced repetition for GCSE. It is also why fifteen minutes a day beats three hours on a Sunday, and why a good revision timetable circles back to each topic several times instead of ticking it off.
How students get it wrong: a timetable that visits each topic exactly once, in order, and finishes the week before the exam — spacing in name only. And cramming, which works for tomorrow's test and is gone by the real one.
Moderate utility: interleaving, elaboration, self-explanation
These three have good evidence in some conditions and less in others. All three are worth using; none replaces the two above.
Interleaving
Interleaving means mixing problem types in one session rather than doing a block of one kind. In maths, that is a page with fractions, ratio and a bit of algebra on it rather than twenty fraction questions in a row, because the exam never tells you which method to use and a mixed page makes you choose. The wrong way: mixing before you can do any of the types alone, which produces confusion rather than practice; and mistaking it for randomness, when it works best as two or three related types alternated on purpose.
Elaborative interrogation
Elaborative interrogation means taking a fact and asking why it is true, then answering. "Why does the rate of reaction increase with temperature?" "Why did the Weimar Republic survive 1923 but not 1933?" It works best in science and history, where facts have reasons, and worst for material with nothing behind it. The wrong way: answering from the textbook rather than from memory, and accepting a shallow answer. The technique is only as good as the "why".
Self-explanation
Self-explanation means talking yourself through each step of a worked example or process — why this step follows that one — in your own words. It suits maths methods, chemistry calculations and anything with a sequence. The wrong way is the common one: reading a worked example, following it, and concluding you could do it. Following is not producing. Cover the next line and say what it must be before you look.
Low utility: highlighting, re-reading, summarising, mnemonics
These are the techniques most students spend most of their revision on. They feel productive because they are easy, and they are easy because they do not require retrieval.
Highlighting
Highlighting marks text for later. On its own it has no reliable benefit over plain reading, and heavy highlighting can hurt, because a page that is mostly yellow contains no decisions. The wrong way: highlighting on the first read, when you do not yet know what matters, and treating a highlighted page as revised. If you highlight, do it once, sparingly, while writing questions, and then close the book.
Re-reading
Re-reading is the default. The second pass feels smoother than the first, and that smoothness reads as knowing, which is the whole problem: the exam asks you to produce the page, not recognise it. It is fine as a first meeting with material and as the way to fill a gap a test has just found. It is a poor fifth pass. The wrong way is the usual way — reading the same chapter again the night before, feeling calm, and discovering in the exam that calm was all it was.
Summarising
Summarising can help when it is done well — choosing what matters, in your own words, without the source open — and most students do not do it that way. They copy the notes onto a smaller page, which is re-reading with a pen. Its real value is as the step before testing: a condensed page becomes a set of questions, which is the approach in how to revise from messy handwritten notes and turn handwritten notes into flashcards. Summarise once, then test from the summary.
Keyword mnemonic
The keyword mnemonic links a new word to a familiar-sounding one through an image; it has a narrow, real use for vocabulary and lists — the order of the planets, the colours of the spectrum. The wrong way is stretching it to cover things that need understanding. A mnemonic for the stages of the cardiac cycle gets you the order; it does not get you a question about what happens when a valve fails.
What the ranking leaves out
The review rated techniques for learning content. Three things outside it matter as much.
- Understanding comes first. Testing strengthens what is there; it cannot install what was never understood. A topic you cannot follow needs a teacher, a textbook or an explanation video before any of the techniques above will do anything.
- Knowing what you do not know. The Education Endowment Foundation's guidance on metacognition puts planning, monitoring and evaluating your own learning at the centre of effective study. The techniques at the top of the table are also the ones that give honest feedback; the ones at the bottom hide it.
- Sleep. Memory is consolidated during sleep, and teenagers need more of it than adults. A late night to fit in another re-read trades the technique for the biology; the NHS's sleep guidance is a better use of the last hour of the day than a fifth pass over the notes.
If you are a parent
Good revision seen from the outside: a closed book, a pen moving, wrong answers being found and written down. A teenager re-reading a highlighted page for two hours looks studious and is doing the least effective thing on the list. There is more on what to look for in how to tell if your teenager is revising.
Putting it together
A week built from the top of the table is not complicated: short daily testing, spaced and mixed across subjects, plus one or two longer sessions for essays and past questions.
- Every day, fifteen to twenty minutes of practice testing — cards due, a blurt, a set of questions — mixed across two or three subjects.
- Each topic comes back at growing intervals; write the dates down when you first learn it, or use an app that does.
- Highlighting and summarising happen once per topic, as the way of making the questions, never as the revision itself.
- Once a week per essay subject, a timed answer that gets marked; once a week for maths and science, a mixed set of exam questions.
- Nothing new in the final week. Only what you have got wrong before.
The bookkeeping in step two is what usually fails first, and it is the part software does well. FacilStudy builds flashcards and a quiz from photographs of your own notes and then picks about fifteen minutes of due work a day across every subject; it is pre-launch, with an early-access list. Anki or a paper diary do the scheduling too. What no tool does is the retrieval — the blank page, the covered line, the card answered before it is flipped — and that is where all the evidence points.
Common questions
- What is the most effective revision technique?
- Practice testing — answering from memory before checking — combined with spacing the sessions out over days and weeks. Those are the only two techniques the 2013 Dunlosky review rated as high utility across ages, subjects and types of test.
- Is highlighting a waste of time?
- As revision, yes; as preparation, no. Highlighting a few key terms while you write questions is fine. Highlighting a page and counting it as a session is the mistake.
- Does re-reading ever help?
- The first time you meet material, and to fill a gap a test has just exposed. Beyond that it produces familiarity rather than memory, and familiarity is what makes students feel ready when they are not.
- What is interleaving and should I use it?
- Mixing question types in one session instead of doing a block of the same kind. Use it once you can do each type on its own; it is especially useful in maths, where the exam never tells you which method to pick.
- How can a parent tell which techniques their child is using?
- Look at what is on the desk. Open notes and a highlighter mean re-reading; a closed book, a pen, cards or a blank page being filled from memory mean testing. Asking "what did you get wrong today?" is a better question than "did you revise?"