--- title: "Why rereading your notes feels like revision and mostly is not - Kerfox" description: "Rereading wins if the test is in five minutes and loses by a week. The experiment that showed it, the survey of what students do, and what the feeling measures." image: "https://www.kerfox.app/og.webp" url: "https://www.kerfox.app/blog/why-rereading-feels-like-working" --- [Kerfox](https://www.kerfox.app/) [THE KERFOX BLOG](https://www.kerfox.app/blog) A NAMED MISCONCEPTION # Why rereading your notes feels like revision and mostly is not The most common revision method in the country is close to the least useful one, and the reason nobody believes that is built into the method itself. By [Eivan Kolchin](https://www.kerfox.app/about) 7 September 2026 ## The experiment that founded the field In 2006 Henry Roediger and Jeffrey Karpicke gave 120 students a short passage of prose to read. Then half of them read it again, and half of them put it away and wrote down as much of it as they could remember, with no answers and no feedback. After that, everyone was tested: forty students five minutes later, forty two days later, forty a week later.[1](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-1) The honest version of the result starts with the part that gets left out. **Rereading won.** Five minutes after studying, the students who had read the passage twice recalled 81% of it, and the students who had read it once and tested themselves recalled 75%. Anyone who has ever crammed successfully for a Friday test knows this, and an article that says rereading does not work is contradicting their experience in its first line. Roediger and Karpicke (2006), experiment 1. Six numbers, all of them on the chart: rereading scores 81, 54 and 42; a single practice test scores 75, 68 and 56. The lines cross somewhere between the first day and the second. Then the lines cross. Two days later the rereaders were on 54% and the tested group on 68%. A week later, 42% against 56%. The group that never reread the passage still recalled, after a week, as much as the rereaders had managed after two days. Over the week the rereaders lost about half of what they had; the tested group lost about a seventh.[1](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-1) The paper’s second experiment pushed harder, with students reading a passage four times against reading it once and testing three times, and found the same shape more sharply: a week later, 61% recalled against 40%. It also asked the students to predict how well they would do. The four-times readers were the most confident group in the study, and they recalled the least.[1](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-1) ## What the feeling of knowing measures That last result is the whole explanation, and it is not a character flaw. The feeling that you know something tracks how easily it comes to mind right now. Rereading is the single most efficient way to make a page come to mind right now, because the page is in front of you, and the sensation of recognising every sentence is indistinguishable from the inside from the sensation of knowing it. Recognition is cheap and leaves almost no trace. Producing the answer from nothing is expensive and leaves the trace. So the two things come apart. The method that maximises the feeling does the least for the memory, and the method that builds the memory feels, while you are doing it, like failure. Karpicke and Blunt showed the same inversion in 2011 with a harder task and a longer horizon: students who practised recalling a science text scored about half again as much a week later as students who spent the same time building concept maps from it, on inference questions as well as recall, and they had predicted the opposite.[3](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-3) The failure of judgement is not limited to choosing a method. Kornell and Bjork found that letting learners set aside the flashcards they judged they had already learned produced small but consistent decreases in later recall against keeping the whole set in rotation, and put the failure squarely in the judgement: dropping a card is only ever as good as your sense of what you know, which is the part that is unreliable.[6](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-6) ## What students actually do Three years after the crossover experiment, Karpicke, Butler and Roediger asked 177 university students how they studied.[2](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-2) Asked to list their strategies, 84% named rereading their notes or textbook, and 55% named it as the one they used most. Eleven per cent listed self-testing at all, and 1% named it as their main method. Given a direct choice after reading a chapter, 57% chose to read it again and 18% chose to test themselves. The authors’ phrase for what is going on is “illusions of competence”. The students were not lazy. Most of them were choosing the method that felt like it worked, in the only way anyone can feel it, and the feeling was wrong. The pattern is not one experiment’s. Rowland’s 2014 meta-analysis pooled 159 comparisons of testing against restudying and found testing ahead by a medium margin, g = 0.50, with the advantage larger when the practice test asked for recall rather than recognition.[4](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-4) And the largest review of study techniques, by Dunlosky and colleagues, rated ten of them and placed rereading and highlighting among the weakest while giving its highest rating to only two: testing yourself and spreading study out.[5](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-5) ## What to do instead The replacement is not exotic and it is not more work. It is the same time, spent producing instead of recognising. - **Close the book before you decide whether you know it.** Read the page once, put it face down, and write what was on it. The gap between what you thought you knew and what came out is the only honest measurement available, and it is the one rereading is designed to hide. - **Then mark it.** Testing yourself without finding out whether you were right is a weaker intervention; Rowland’s pooled data found the benefit larger with feedback.[4](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-4) Open the book after the attempt, not instead of it. - **Expect it to feel worse.** A session that ends with you unsure is a session that did the work. The four-times readers in 2006 felt best and remembered least, and the feeling was the last thing that should have been trusted. - **Reread on purpose, once, at the start.** The crossover says rereading is fine as a first pass through material you have never met. It says nothing kind about a fourth pass. ## What this does not say It does not say cramming is useless. The five-minute result is real, and if the test is tomorrow morning the loan does not fall due until after it. What it says is that the same method used for a subject you have to keep, across modules that build on each other, charges its interest twice. It does not say these numbers are yours. The 2006 experiment used a prose passage recalled freely, in a laboratory, by undergraduates, and the practice test carried no feedback, which usually makes retrieval work better rather than worse. A meta-analysis of 159 comparisons is a much wider base, and the spread between studies inside it is very wide.[4](https://www.kerfox.app/blog/why-rereading-feels-like-working#source-4) The direction is settled. The size, for you, on your subject, is not a number anyone can give you. And it does not say that Kerfox, or any app, has been shown to change any of this. Nobody has studied it. What can be said is that every question in the app shows the answer after the attempt and not before, and this experiment is the reason why. ## Sources 1. Roediger & Karpicke (2006). Test-Enhanced Learning: Taking Memory Tests Improves Long-Term Retention. Psychological Science, 17(3), 249-255. [doi.org/10.1111/j.1467-9280.2006.01693.x](https://doi.org/10.1111/j.1467-9280.2006.01693.x)Students who tested themselves recalled 61 per cent of a passage a week later against 40 per cent for students who reread it four times, and the ordering was the other way round at five minutes. The rereaders were also the more confident group about what they would remember. 2. Karpicke, Butler & Roediger (2009). Metacognitive strategies in student learning: Do students practise retrieval when they study on their own?. Memory, 17(4), 471-479. [doi.org/10.1080/09658210802647009](https://doi.org/10.1080/09658210802647009)Asked how they study, 177 university students overwhelmingly named rereading their notes or textbook, 84 per cent listing it and 55 per cent as their main method, while 11 per cent listed self-testing and 1 per cent named it their main method; offered a direct choice after reading a chapter, most chose to reread. A self-report survey at one American university, and the authors’ own phrase for the pattern is illusions of competence. 3. Karpicke & Blunt (2011). Retrieval Practice Produces More Learning than Elaborative Studying with Concept Mapping. Science, 331(6018), 772-775. [doi.org/10.1126/science.1199327](https://doi.org/10.1126/science.1199327)With study time held equal, students who practised recalling a science text scored about half again as much a week later as students who built concept maps from it, on inference questions as well as recall, and they had predicted the opposite. A formal Comment was published on this paper in the same journal; it did not overturn the result, and it is worth knowing the paper is argued over. 4. Rowland (2014). The Effect of Testing Versus Restudy on Retention: A Meta-Analytic Review of the Testing Effect. Psychological Bulletin, 140(6), 1432-1463. [doi.org/10.1037/a0037559](https://doi.org/10.1037/a0037559)Pooling 159 comparisons, testing yourself beat rereading by a medium margin, g = 0.50, with the advantage larger when the practice test asked for recall rather than recognition. The spread between studies is very wide. 5. Dunlosky et al. (2013). Improving Students’ Learning With Effective Learning Techniques: Promising Directions From Cognitive and Educational Psychology. Psychological Science in the Public Interest, 14(1), 4-58. [doi.org/10.1177/1529100612453266](https://doi.org/10.1177/1529100612453266)A review rating ten study techniques gave its highest recommendation to only two, testing yourself and spreading study out, while highlighting and rereading came out among the weakest. Interleaving and self-explanation were rated moderate rather than high, which is often misquoted upward. 6. Kornell & Bjork (2008). Optimising self-regulated study: The benefits - and costs - of dropping flashcards. Memory, 16(2), 125-136. [doi.org/10.1080/09658210701763899](https://doi.org/10.1080/09658210701763899)Letting learners set aside the cards they judged they had already learned produced small but consistent DECREASES in later recall against keeping the whole set in rotation. The authors put the failure in the judgement itself: dropping has a compelling logic, and it is only ever as good as a learner’s sense of what they actually know, which is the part that is unreliable. ## Read next - [ HOW TO STUDY ### The same hours, spread out: how far apart to space revision Four hours across four days beats four hours in one evening on any test more than a day away. The evidence, the best gap, and why the worse option feels better. 7 September 2026 ](https://www.kerfox.app/blog/same-hours-spread-out) - [ STUDY AND WELLBEING ### An extra hour of revision costs about eight minutes of sleep Five hundred students kept diaries for a fortnight. Studying more than usual cost little, and it hurt the next day only when the hour had come out of sleep. 7 September 2026 ](https://www.kerfox.app/blog/an-extra-hour-of-revision) - [ THE MARK SCHEME WORD ### Denatured, not killed: the enzyme word the mark scheme refuses AQA’s GCSE Biology mark schemes credit “denatured” and carry the line “do not accept enzyme(s) killed”. The line, the reason, and the words that are allowed. 7 September 2026 ](https://www.kerfox.app/blog/denatured-not-killed) WHERE THIS IS BUILT IN Kerfox marks written answers against the board’s own words, so the word a mark scheme refuses is the word the app refuses too, with the reason. It is free, and it is in closed testing. [Join the waitlist](https://www.kerfox.app/waitlist)