How should exam revision change when time is short?
When time is short, drop re-reading entirely and spend nearly all remaining hours on retrieval practice, testing yourself instead of reviewing notes, with whatever spacing the remaining days allow. A meta-analysis of 22 classroom studies covering more than 3,000 students found a moderate advantage for spaced over massed practice (d = 0.54), and the effect tended to grow with a longer gap before the test, which means spacing still helps even in a compressed window, just proportionally less than it would with weeks to work with. Retrieval practice, by contrast, doesn't lose its power under time pressure. A classroom study that tested it directly against re-reading with real material found a clear advantage for testing regardless of how the sessions were spaced.
Is it too late for spacing if the exam is only a few days away?
A few days is still enough time to space, just on a compressed schedule rather than the days-to-weeks version. The classroom meta-analysis found effect sizes were generally larger with longer retention intervals, but the underlying advantage of spaced over massed practice showed up across a range of interval lengths, not only long ones. Two review sessions with a night's sleep between them still outperforms one long session covering the same material, because the gap, even a short one, forces a small amount of forgetting that makes the next relearning attempt stronger.
A compressed schedule that still uses spacing: if you have three days, don't spend all three doing first-pass reading. Spend day one on first-pass reading plus immediate retrieval practice (testing yourself the same day you first learned it). Spend day two almost entirely on retrieval practice across everything covered so far, with new material only where genuinely uncovered. Spend the final day on retrieval practice exclusively, prioritized by what you got wrong on day two. Each day is a spaced repetition of the same material through a different retrieval attempt, not a fresh read-through.
Should I keep re-reading my notes with limited time left?
No. Re-reading feels productive precisely because it's low-effort and the material looks increasingly familiar with each pass, but that familiarity is recognition, not recall, and recognition is not what an exam tests. With limited time, every hour spent re-reading is an hour not spent building the specific skill, cold recall with nothing in front of you, that the exam will actually require.
The classroom study on retrieval practice used a testing procedure with accuracy feedback, students kept testing on material until they got it fully correct, rather than a fixed number of passes. That structure is worth copying under time pressure: don't decide in advance how many times you'll review something. Test it, and keep retesting specifically the items you get wrong, until you get them right. This concentrates your remaining hours on your actual weak points instead of spreading them evenly across material you already know.



