Short answer
Spaced repetition is a study method where you review the same material several times with growing gaps between sessions, instead of cramming it all at once. Research on distributed practice has found that spreading review out supports longer-lasting memory than massed study, and that the best gap gets longer the further away the test is.
Key takeaways
- Spaced repetition means reviewing material several times with gaps between sessions, and the gaps usually grow longer.
- A meta-analysis by Cepeda and colleagues (2006) found that the review gap giving the best retention grew as the time until the final test grew.
- A 2015 replication of Ebbinghaus's forgetting curve produced results similar to the original data from 1880.
- A simple school schedule reviews a chapter after one day, a few days, a week and a few weeks.
- Each review session works best as active recall, answering from memory first, rather than rereading.
What is spaced repetition?
Spaced repetition is returning to the same material at planned intervals, with each gap a little longer than the last. Researchers often call the broader idea spaced practice or distributed practice, and contrast it with massed practice, which is doing all the study in one block.
Spaced repetition is often linked with flashcard apps, but the idea works just as well with whole school chapters. A student who studies a chapter on Monday and returns to it on Tuesday, Friday and the following Friday is using spaced repetition, no software needed.
Why does spacing out review beat cramming?
Spacing beats cramming because memory fades over time, and a review that comes after some forgetting does more work than one that comes straight away. Cramming can get a student through a test the next morning, but much of it is gone a few weeks later.
The fading itself is old news. Hermann Ebbinghaus measured his own forgetting in the 1880s, and Murre and Dros (2015) repeated his experiment, relearning lists after intervals from 20 minutes to 31 days. Their results were similar to his original forgetting curve. The paper also notes that material which seems forgotten can still be relearned faster than new material, which is one reason a review is worth doing even when a chapter feels lost.
Cepeda and colleagues (2006) pooled 839 assessments of distributed practice from 317 experiments. Their analysis suggests the best gap between study sessions depends on how long the material needs to be remembered: the longer the wait until the test, the longer the best gap. Dunlosky and colleagues (2013) rated distributed practice as one of two high-utility study techniques.
What is a simple spaced repetition schedule for school chapters?
A simple spaced repetition schedule reviews a chapter about a day after first studying it, then after a few days, a week, and a few weeks. The intervals below are a suggested starting point, not a schedule prescribed by research, so adjust them to the exam date and how well each review goes.
| Review | When | What to do | Time |
|---|---|---|---|
| First study | Day 0 | Read the chapter, explain it back, test yourself | About an hour |
| Review 1 | Day 1 | Blank-page recall, then check the book | 10 to 15 minutes |
| Review 2 | Day 3 or 4 | Answer end-of-chapter questions from memory | 15 minutes |
| Review 3 | Day 7 to 10 | Short practice paper, then fix mistakes | 20 to 30 minutes |
| Review 4 | Day 21 to 30 | Mixed questions with other chapters | 20 to 30 minutes |
| Final check | The week before the exam | Revisit only the questions missed earlier | 15 minutes |
If a review goes badly, shorten the next gap. If it goes smoothly, the next gap can stretch a little further.
Here is how that looks in a real week. A student studies a science chapter on Monday evening, does a five-minute blank-page recall of it on Tuesday, answers the chapter's end questions on Thursday and takes a short practice paper on it the following Monday. Each review is small, but together they mean the chapter has been pulled from memory four times before the exam, not once.
How do you fit a spaced repetition schedule around many subjects?
Fit it in by keeping each review short and writing review dates on a calendar the moment a chapter is first studied. Most days then hold one new chapter and two or three quick reviews of older ones.
- Plan from the exam date backwards. Make sure every chapter gets at least three reviews before the exam.
- Mix subjects in a day. A science review, a maths review and a history review in one evening is easier to sustain than three of the same.
- Review weak chapters more often. A chapter that keeps going badly earns shorter gaps than one that is already solid.
- Keep a simple log. A line per chapter with review dates and how it went is enough.
For building this into a weekly plan, see our study timetable guide.
What should you do in each spaced practice session?
In each spaced practice session, test yourself first and only then open the book. Rereading during a review brings back the comfortable feeling of familiarity without showing what has actually been forgotten.
This is where spacing meets active recall: the schedule decides when to review, and recall decides how. A blank page, the textbook's end-of-chapter questions or a short practice paper all work. More methods are in our study skills guides.
What if the exam is only a few weeks away?
If the exam is close, keep the same pattern with shorter gaps. The Cepeda and colleagues (2006) analysis suggests the best gap scales with how far away the test is, so a nearer exam calls for tighter spacing, such as reviews after one day, three days and a week.
Even with little time, two or three short spaced reviews of a chapter are a better use of an evening than one long reread of it the night before.
How can StudyMate help with chapter reviews?
StudyMate AI can supply the review itself. On a review day, a student can generate a practice paper from that chapter at the difficulty they choose and get an instant, detailed evaluation. Progress reports also show how each chapter went, with a "what to study next" list that puts the weakest chapter first, which helps decide which chapters need shorter gaps.
Frequently Asked Questions
How many times should you review a chapter before an exam?
Three to five spaced reviews is a practical target for most school chapters. Chapters that keep going badly need more, and chapters that are already solid can manage with fewer. There is no single research-set number for every subject.
Is spaced repetition only for flashcards?
No. Spaced repetition is about timing, so it works with any review method. Blank-page recall, end-of-chapter questions and practice papers can all be scheduled the same way flashcards are.
What is the difference between spaced repetition and spaced practice?
The terms overlap. Spaced practice, or distributed practice, is the general research term for spreading study out over time. Spaced repetition usually refers to a planned schedule of reviews with gaps that grow.
Can spaced repetition help the night before an exam?
Not much, because spacing needs days between sessions. The night before is best used for a calm check of earlier mistakes and a good night's sleep, with the spaced reviews planned well ahead next time.
Sources
- 1Cepeda, Pashler, Vul, Wixted & Rohrer, Psychological Bulletin (2006). Distributed practice in verbal recall tasks: A review and quantitative synthesis
- 2Murre & Dros, PLOS ONE (2015). Replication and Analysis of Ebbinghaus' Forgetting Curve
- 3Dunlosky, Rawson, Marsh, Nathan & Willingham, Psychological Science in the Public Interest (2013). Improving Students' Learning With Effective Learning Techniques