Spaced repetition, explained: why cramming fails

Cramming has one genuine superpower: it gets facts into your head quickly. Its fatal flaw is that they leave almost as fast. Psychologists have measured this since the 1880s, when Hermann Ebbinghaus mapped the 'forgetting curve' — without review, you lose most of what you learn within days.

The fix isn't revising more. It's revising at the right moments.

The forgetting curve, and the trick that beats it

Each time you successfully recall something just as you're starting to forget it, two things happen: the memory gets stronger, and it decays more slowly afterwards. So the ideal review schedule starts tight and stretches out — recall a fact after a day, then three days, then a week, then a month. Five or six well-timed reviews can keep something solid for an entire exam season.

That schedule is what 'spaced repetition' means. Algorithms like SM-2 (the one behind Anki, and behind SwipeLearn's review system) track every item you've studied and compute when you should see it next, based on how easily you recalled it last time. Struggle, and it comes back tomorrow; nail it, and it might not return for weeks.

Why this beats cramming for GCSEs specifically

GCSEs are a volume problem. You're sitting maybe eight to ten subjects, each with hundreds of facts, methods and definitions, examined over a few weeks. No human can cram that in the final fortnight — there isn't enough fortnight.

Spaced repetition turns that mountain into a manageable daily trickle, starting months out. Ten minutes a day from January quietly compounds into hundreds of secure facts by May — while the crammer is meeting half their specification for the second time ever, the night before the paper.

One detail worth knowing: a good system also plans around your exam date. There's no point a memory being scheduled for its next review in July if your paper is in June — SwipeLearn caps review gaps so everything you've learnt gets a final pass in the run-up to your exam.

How to actually use it

You can run spaced repetition by hand with flashcards and a calendar (look up the Leitner box system), but the admin defeats most people. The realistic version is an app that schedules for you, a small daily habit you genuinely keep, and honest self-testing — if you peeked, it doesn't count as recall.

Whichever tool you use: start now, keep it small, and trust the schedule. The whole point is that future-you remembers what present-you only had to look at for thirty seconds.