Study skills
What is spaced repetition?
Quick answer
Spaced repetition means reviewing what you have learned several times with gaps in between, instead of cramming it all at once. The gaps help memories last longer.
In one sentence
Spaced repetition is coming back to the same material again and again, with gaps that get longer each time.
Explained
In the 1880s, the German psychologist Hermann Ebbinghaus tested his own memory and noticed that we forget new information quickly at first, then more slowly. This pattern is known as the forgetting curve. He also found that reviewing material again after a gap slowed the forgetting down.
Since then, many studies have found the same thing, often called the spacing effect: if you have two hours to learn something, splitting them into four half-hour sessions spread over a couple of weeks usually beats one two-hour session. The total time is the same; the timing is different.
Why? When you return to a topic after a gap, you have forgotten a little, so remembering takes effort. That effort helps the memory stick. Spacing works best when each review is a self-test, using active recall, not just a reread.
There is no single perfect schedule. A sensible starting pattern is to review new material the next day, then a few days later, then after a week, then after a few weeks. If something is easy, leave longer gaps; if you keep getting it wrong, review it sooner.
clock
notebook
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Examples
A simple spacing plan for one topic:
| When | What to do |
|---|---|
| Day 1 | learn it and make questions or flashcards |
| Day 2 | test yourself, fix mistakes |
| Day 5 | test again |
| Day 12 | test again |
| Day 30 | final check before the exam |
The Leitner box system (named after Sebastian Leitner, who described it in the 1970s): use three boxes. New flashcards start in box 1, reviewed every day. Get one right and it moves to box 2 (every few days), then box 3 (once a week). Get it wrong and it goes back to box 1.
Common mistakes
- Leaving all reviews until the last week. Spacing needs time, so start early.
- Reviewing by rereading. Each review should be a quiz, not a skim.
- Never changing the gaps. Spend more time on hard material and less on what you know well.
Quick quiz
Spaced repetition
Check what you know with 3 quick questions.
Question 1 of 3
Which plan uses spaced repetition?
Practise it
Try it
Print revision flashcards
Plan your gaps with a revision timetable.
For grown-ups
Related topics
Active recall
Active recall means testing yourself by pulling information out of your memory, instead of rereading it. It is one of the best-supported ways to revise.
Flashcards
Flashcards are small cards with a question on one side and the answer on the other. They work best when you answer from memory before you flip.
Revision timetable
A revision timetable is a plan of what to revise and when. Good ones use short sessions, mix subjects, revisit topics after gaps and leave time for rest.
Exam technique
Exam technique is the set of skills for answering the paper well on the day, such as reading questions carefully, using marks to plan time and checking your work.
Note-taking
Good notes are short, in your own words and organised so you can test yourself later. Methods like Cornell notes build in questions and a summary.
Growth mindset
A growth mindset is the belief that abilities can improve with practice, good strategies and help. A fixed mindset is the belief that you either have a talent or you don't.