Spaced repetition means revisiting material in separate sessions over time. You might review a topic tomorrow, again a few days later and then the following week, adjusting the gaps to what you can still recall. Flashcards are one option; problems, explanations and essay plans can also be revisited. The aim is to retain and use what you learn, not simply to clear a daily queue.
The forgetting curve (and why it matters)
Hermann Ebbinghaus studied forgetting by learning lists of nonsense syllables and later relearning them. The measure was the time or effort saved during relearning, not the percentage of a lecture a student would still remember.
A 2015 replication in PLOS ONE used the same savings method with one participant. It found a broadly similar pattern. Neither experiment supplies a universal timetable for forgetting meaningful course material.
The practical point is to check knowledge again after a delay. A successful answer immediately after reading does not tell you how accessible it will be next week.
What is spaced repetition?
Spaced repetition distributes reviews rather than placing all practice in one sitting. You cannot observe the exact instant before forgetting. Instead, use your answers to decide whether to extend an interval, shorten it or revisit the explanation before another attempt.
Why spacing beats massing
A 2006 review in Psychological Bulletin synthesised experiments on distributed practice in verbal recall. It found a benefit from spacing and a relationship between the useful practice interval and the later retention interval. That supports spreading practice; it does not prescribe one exact schedule for every subject or exam date.
The interval grows with each successful recall. A new piece of information might need reviewing after one day, then three days, then a week, then three weeks. Items you keep getting wrong stay on shorter intervals.
Recall, not rereading
Spacing describes when you practise. Retrieval describes what you do during a review: try an answer before checking it. In Roediger and Karpicke's 2006 experiments, retrieval practice improved delayed recall of prose passages relative to repeated study. Reading remains useful when you need to learn or clarify something; repeated familiarity alone is not a test of recall.
What does spacing add to a single long session?
A long session may make answers available immediately, but it does not check whether they remain available after a delay. Returning on another day gives you that check and a chance to repair gaps while there is still time.
Nate Kornell's 2009 flashcard experiments compared spaced and massed practice. Spacing improved learning in the tasks studied, while learners' impressions did not always match their later performance. Judge your own routine by delayed answers, not only by how fluent the final repetition feels.
For a subject assessed through extended reasoning, use the remembered material in a full response as well. Our guides to law school in Canada and law degrees in Australia distinguish knowledge of a rule from applying it to a problem.
How to schedule your reviews
A simple schedule without an app
The following is an example to adapt to your deadline and your answers:
- Day 1: Learn the material
- Day 2: First review
- Day 5 to 7: Second review
- Day 14 to 16: Third review
- Day 30+: Fourth review, and so on
If you get something wrong during a review, move it back to a shorter interval. If you get it right easily, you can extend the gap. Put the intervals into your study schedule so they do not quietly slip.
Letting an app do the maths
Dedicated flashcard apps manage this automatically. Anki's manual describes the mechanism plainly: you rate how well you recalled each card, and the time until the next review gets longer and longer, from days to weeks to months. For students with large volumes of material across multiple subjects, this automation is worth the small learning curve. The apps that do the scheduling are compared for UK students and for Australian students.
Flashcards as the practical tool
Flashcards provide a convenient format for active recall: a question on one side and an answer on the other. They become retrieval practice when you attempt the answer before revealing it; flipping straight to the back skips that step.
Good flashcards are specific and focused on a single idea, and we cover the craft in how to make flashcards from your notes. Bad flashcards are dense paragraphs that you cannot realistically recall in one go. When creating flashcards:
- Keep each card to one concept or fact
- Write the question in your own words
- Avoid copying text directly from slides or textbooks
A worked example: one module over four weeks
Suppose the module is introductory microeconomics and the exam is in five weeks. This is a planning example, not a prediction of how quickly you will learn.
- Week 1. After each of two lectures, make a small set of questions from the important ideas and any points you could not explain. Review each set the following day, checking your answers. The number of cards should follow the material and the time you have.
- Week 2. Review the first set before adding cards from new lectures. If an elasticity question keeps failing, check whether the problem is the definition, the calculation or the question's wording.
- Week 3. Attempt a new elasticity problem without the worked solution. Recalling the definition does not by itself establish that you can choose and use the formula.
- Week 4. Check whether the review queue fits your available time. Pause new cards if necessary and give priority to gaps relevant to the exam.
- Revision week. Combine delayed reviews with past-paper questions and full answers. Keep checking difficult material instead of assuming the schedule has made it secure.
Common mistakes to avoid
A few patterns consistently undermine spaced repetition for students new to it:
- Leaving all practice until the final sitting: begin earlier when possible. With a short deadline, separate a few focused attempts and check them carefully. The exam preparation guide helps prioritise; students in Ireland should also check their own assessment and revision arrangements.
- Passive review: Flipping to the answer immediately without attempting recall first wastes the exercise.
- Skipping weak cards: It is tempting to keep reviewing what you already know. The harder cards are the ones that need the most attention.
- Too many cards at once: large additions create future reviews. Use the time your existing queue takes to decide how much new material to add.
- Trusting the feeling: Kornell's experiments show that learners' impressions can favour massing even when spacing produces better later performance. Use delayed answers to assess your routine.
Making it part of your routine
Set aside a repeatable review slot in your study schedule. Start small enough to include checking answers and working through errors. A missed day is a reason to adjust the queue, not to abandon the method or rush through every card without thinking.
Notibo can generate flashcards from recordings and uploaded documents. Verify the questions against your material before relying on them. Cards cannot currently be edited individually, so put corrections and any missing questions in your own notes. Generated cards are a starting point, not evidence that the whole course is covered.
For how Notibo makes and schedules the cards, see flashcards from lectures and slides. The review schedule is part of Pro; the plans are on the pricing page.