Revision that works

The short version

Three habits do most of the work, and the research behind them is unusually consistent:

1. Retrieval. Test yourself instead of reading again.
2. Spacing. Come back to a topic over days and weeks, not all in one evening.
3. Interleaving. Mix topics in a session instead of doing one at a time.

All three feel harder than the alternative while you're doing them. That feeling is part of why they work, and part of why most students don't use them.

Why rereading feels better than it works

Reading your notes again makes them feel familiar, and familiar feels like knowing. But recognizing something on the page is not the same as producing it in an exam with the page gone.

Students lean on rereading anyway. In a survey of 177 university students, 84% said they reread as a study strategy and 55% named it their main one; 11% said they practiced recalling the material (Karpicke, Butler and Roediger, 2009).

A large review of ten common study techniques rated rereading and highlighting as low utility, and practice testing and spaced practice as the two with high utility (Dunlosky and colleagues, 2013).

Rereading isn't useless. It's a fine first pass. It's a poor way to check that you know something, because it never asks you to.

Retrieval means testing yourself

Retrieval means pulling something out of memory: answering a question, writing what you remember on a blank page, explaining a process without looking.

In one well-known experiment, students read a short passage, then either read it again or wrote down what they could remember. After five minutes, the rereaders did slightly better. After a week, the students who had tested themselves remembered 56% against 42% (Roediger and Karpicke, 2006). In a second experiment, the group that read the passage most often felt the most confident and remembered the least.

A later study compared retrieval with making a concept map, with the text open. A week later, the retrieval group did better, on factual and on inference questions. Most students had expected the concept map to work as well or better (Karpicke and Blunt, 2011).

What it looks like for IB revision:

• Do questions before you feel ready, then check them against the markscheme.
• Close the notes and write down everything you know about a subtopic. Then open them and look at what you missed.
• Use flashcards for definitions, formulas and command-term vocabulary, answering before you turn the card.

Getting something wrong while testing yourself is not wasted time. Checking the answer straight afterwards is what makes the attempt count.

Spacing means coming back later

The same hours of study are worth more spread out than bunched together. A review of 317 experiments found spaced study beat massed study, and that the best gap between sessions grows with how long you need to remember (Cepeda and colleagues, 2006).

A follow-up with more than 1,350 people put numbers on it. For a test one week away, the best gap was roughly a fifth to two fifths of that week. For a test a year away, it was roughly a twentieth to a tenth of the year, which is several weeks (Cepeda and colleagues, 2008).

For an exam months away, that means reviewing a topic a few days after you learn it, then again a week or two later, then again a month or so after that. Cramming the night before can get you through a test the next morning. It does little for an exam in May.

Why memory fades, and why that helps

Memory fades quickly at first and then more slowly. Hermann Ebbinghaus measured this on himself in 1885, and a replication in 2015 found much the same curve (Murre and Dros, 2015).

One useful way to think about it separates two strengths. Storage strength is how well something is learned. Retrieval strength is how easily you can reach it right now. Retrieval strength fades without use. Recalling something just as it was getting hard to reach builds storage strength more than recalling it while it's still fresh (Bjork and Bjork, 1992).

That is the reason to come back to a topic once you've started to forget it, not before. It's also why quick fire's topic strength fades when you don't practice: it is an estimate of retrieval strength, not a score you keep. See quick fire.

Interleaving means mixing topics

Doing ten questions on one method, then ten on the next, feels productive. Mixing them feels slower. In one study on math, students who practiced one problem type at a time scored 89% during practice against 60% for those who mixed them. A week later, the mixed group scored 63% and the blocked group 20% (Rohrer and Taylor, 2007).

The likely reason: when every question in a block uses the same method, you never have to decide which method a question needs. Exam papers ask you to decide every time.

People rarely believe this about themselves. In a study on recognizing painters' styles, 78% of participants learned better from mixed examples, and 78% said they thought the grouped examples had worked as well or better (Kornell and Bjork, 2008).

Interleave once you've learned the topics separately. Mixing topics you've never met is just confusing.

Hard is not the same as wrong

Robert Bjork calls these desirable difficulties: conditions that slow your progress during study but improve what you keep (Bjork, 1994; Bjork and Bjork, 2011). Testing, spacing and mixing all make a session feel worse than rereading would. Judge a method by what you can do a week later, not by how the session felt.

The difficulty has to be one you can get through. A question far beyond what you've learned teaches very little; one you can just about answer, with a check afterwards, teaches a lot.

A week of revision that uses all three

One way to put it together for a subject, a few months before exams:

• Monday: learn or relearn one subtopic from the notes. Close them and write down what you remember.
• Tuesday: ten exam-style questions on that subtopic, marked against the markscheme.
• Wednesday: flashcards for the week's definitions and formulas.
• Thursday: a mixed set across the last month's topics, with no topic labels.
• Friday: go back to what you got wrong this week, then try one new question on each.
• Weekend: a few quick questions on something from last month you haven't touched since.

None of this needs any particular tool. Paper, a pen and a markscheme will do.

Where Augment fits

If you use Augment, this is what each part is for:

• Retrieval with a markscheme: the question bank. You answer, reveal the markscheme and mark yourself.
• Spacing for facts: flashcards schedule each card for just before you'd forget it.
• Retrieval and spacing for the basics: quick fire rounds pick questions that are due or were missed, and strength fades without practice.
• Interleaving: worksheets build a set of questions across the topics you choose. Shuffle it so the topics are mixed.

Sources

• Bjork, R. A. (1994). Memory and metamemory considerations in the training of human beings. In J. Metcalfe and A. P. Shimamura (Eds.), Metacognition: Knowing about knowing (pp. 185–205). MIT Press.
• Bjork, E. L., and Bjork, R. A. (2011). Making things hard on yourself, but in a good way: Creating desirable difficulties to enhance learning. In M. A. Gernsbacher and others (Eds.), Psychology and the real world (pp. 56–64). Worth. Free copy from the authors' lab.
• Bjork, R. A., and Bjork, E. L. (1992). A new theory of disuse and an old theory of stimulus fluctuation. In A. F. Healy, S. M. Kosslyn and R. M. Shiffrin (Eds.), From learning processes to cognitive processes (Vol. 2, pp. 35–67). Erlbaum.
• Cepeda, N. J., Pashler, H., Vul, E., Wixted, J. T., and Rohrer, D. (2006). Distributed practice in verbal recall tasks: A review and quantitative synthesis. Psychological Bulletin, 132(3), 354–380. doi:10.1037/0033-2909.132.3.354
• Cepeda, N. J., Vul, E., Rohrer, D., Wixted, J. T., and Pashler, H. (2008). Spacing effects in learning: A temporal ridgeline of optimal retention. Psychological Science, 19(11), 1095–1102. doi:10.1111/j.1467-9280.2008.02209.x
• Dunlosky, J., Rawson, K. A., Marsh, E. J., Nathan, M. J., and Willingham, D. T. (2013). Improving students' learning with effective learning techniques. Psychological Science in the Public Interest, 14(1), 4–58. doi:10.1177/1529100612453266
• Ebbinghaus, H. (1885). Über das Gedächtnis. Translated as Memory: A contribution to experimental psychology (1913). Full text.
• Karpicke, J. D., and Blunt, J. R. (2011). Retrieval practice produces more learning than elaborative studying with concept mapping. Science, 331(6018), 772–775. doi:10.1126/science.1199327
• Karpicke, J. D., Butler, A. C., and Roediger, H. L. (2009). Metacognitive strategies in student learning: Do students practice retrieval when they study on their own? Memory, 17(4), 471–479. doi:10.1080/09658210802647009
• Kornell, N., and Bjork, R. A. (2008). Learning concepts and categories: Is spacing the "enemy of induction"? Psychological Science, 19(6), 585–592. doi:10.1111/j.1467-9280.2008.02127.x
• Murre, J. M. J., and Dros, J. (2015). Replication and analysis of Ebbinghaus' forgetting curve. PLOS ONE, 10(7), e0120644. doi:10.1371/journal.pone.0120644
• Roediger, H. L., and Karpicke, J. D. (2006). Test-enhanced learning: Taking memory tests improves long-term retention. Psychological Science, 17(3), 249–255. doi:10.1111/j.1467-9280.2006.01693.x
• Rohrer, D., and Taylor, K. (2007). The shuffling of mathematics problems improves learning. Instructional Science, 35(6), 481–498. doi:10.1007/s11251-007-9015-8