To revise effectively, test yourself instead of rereading your notes, spread your revision over several days and weeks, mix different topics and problem types in each session, and explain ideas in your own words. All four have much better evidence behind them than rereading or highlighting.
They also feel harder, which is why most students avoid them. Rereading is comfortable because the material looks familiar. Effective revision is less comfortable because it shows you, every session, what you can't do yet.
This guide covers why rereading falls short, the revision techniques that work, which to use for each subject, how to review notes after class, a 45-minute weekly review routine, and a sample revision timetable.
Why rereading your notes isn't revision
Rereading makes notes feel familiar, and familiarity feels like knowledge. But the exam doesn't show you your notes. It asks you to produce the answer.
In a classic 2006 study, students who read a science passage once and then tried to recall it remembered 56% of it a week later. Students who read it twice remembered 42%. On a test five minutes after studying, the rereaders were slightly ahead, which is exactly why rereading is so convincing in the moment.
Most students still reread. In a 2009 survey of 177 college students, a majority said they repeatedly read their notes or textbook, and relatively few tested themselves. A 2013 review of ten common techniques rated rereading and highlighting low utility and practice testing and spaced practice high utility. Our comparison of active recall vs passive reading goes into why.
Read once to understand. After that, every revision session should make you retrieve something.
How to revise effectively: the best revision techniques
Self-testing (active recall)
Anything that makes you produce the answer before you see it counts:
- Blank-page recall: write everything you remember about a topic, then check your notes and add what you missed in a different color.
- Questions from headings: turn each heading in your notes into a question, cover the content, and answer.
- Flashcards: one fact or idea per card, and say the answer before you flip.
- Past papers and practice questions: the closest match to the real exam.
Always check your answers. Testing without feedback can lock in mistakes.
Spaced revision
Revisit each topic several times with gaps in between, instead of covering it once in a long session. Each return catches the topic before it slides too far down the forgetting curve. In a study of more than 1,350 people, Nicholas Cepeda and colleagues found that the best gap depends on how far away the test is: about 20–40% of the time until a test a week away (one to three days), falling to 5–10% for a test a year away (roughly three to five weeks). The closer the exam, the shorter the gaps. Our spaced repetition guide shows how to schedule reviews.
Interleaving (mixed practice)
Mix topics or problem types within a session instead of doing all of chapter 3, then all of chapter 4. Mixed practice forces you to decide which method a problem needs, which is what exams ask. It also feels worse while you do it:
Blocked practice feels better; mixed practice lasts
Share of math problems solved correctly during practice and on a test one week later
- Blocked practice
- Mixed (interleaved) practice
View data
| When measured | Blocked practice | Mixed (interleaved) practice |
|---|---|---|
| During practice | 89% | 60% |
| Test 1 week later | 20% | 63% |
In that study, college students learned to find the volumes of unusual solids. The blocked group looked far better during practice, then scored 20% a week later against 63% for the mixed group. Interleaving helps most with problems that look alike but need different methods; see our interleaving guide for when it doesn't help.
Elaboration: ask "why?"
For each fact, ask why it's true and how it connects to something you already know. "Why does increasing temperature speed up this reaction?" forces you to use what you've learned about collision theory, not just repeat a sentence. The 2013 review rated this moderately useful, with the strongest evidence for factual material. Our guide to elaborative interrogation has question templates.
Practice in the exam's format
If the exam has six-mark questions, practice six-mark questions. If it's timed essays, write timed essays. Mark your answers against official mark schemes when they exist, and keep a list of the mistakes you repeat.
Which revision technique works best for each subject?
| Subject | Best revision methods | Try this |
|---|---|---|
| Maths, physics | Mixed problem sets, redoing errors from scratch | Shuffle 10 problems from three chapters; no worked examples open |
| Biology, chemistry | Drawing processes from memory, flashcards for terms, "why" questions | Draw the stages of mitosis from memory, then check |
| History, politics | Timelines from memory, essay plans with evidence | Plan three past essay questions in 10 minutes each |
| English literature | Quote flashcards, theme maps, timed paragraphs | Learn five quotes per theme and what each one shows |
| Languages | Spaced vocabulary cards in both directions, speaking aloud | Describe your weekend out loud using this week's vocabulary |
| Law, medicine, professional exams | Question banks and case scenarios | Do 20 mixed questions, then review every explanation |
Professional exams often come in several sections that you take one at a time. If you're preparing for the CPA, a section-by-section CPA study schedule applies these same methods.
How to review your notes effectively after class
The first review should happen within a day, while you can still fill gaps from memory.
- Close your notes and write the main points of the class on a blank page. Five to ten minutes is enough.
- Open your notes and compare. Add what you missed in a different color.
- Turn the gaps into questions ("What are the three stages of cellular respiration?") and put them in your flashcards or a question list for the weekly review.
- Fix anything you didn't understand now: check the textbook, ask a classmate, or note it for your teacher.
If you take notes in the Cornell format, the cue column is already a list of questions; cover the right side and answer. Our Cornell note-taking guide shows the layout.
How to do a weekly review for studying
A weekly review is a fixed session, once a week, where you recall the week's material from memory, quiz yourself on earlier weeks, and plan the next few days around what you missed. It isn't the productivity-style weekly review of your to-do list. This one is aimed at memory, with five minutes of planning at the end.
It's the simplest way to build spaced review into a busy term without tracking a review date for every topic. It also counters a common pattern: in a 2012 survey of 324 undergraduates, students tended to study whatever deadline was coming next, and low performers did so most of all.
What to have ready
- The week's topic list: lecture titles, the syllabus, or chapter headings
- Your notes and any problem sets
- Your running list of questions or flashcards (if you don't have one yet, this week's gaps will start it)
- A blank page and a timer
The 45-minute routine
Do it at the same time each week, such as Sunday afternoon.
| Step | What to do | Time |
|---|---|---|
| 1. List | Write the week's topics for each course from the syllabus or lecture titles. Don't reread notes. | 5 min |
| 2. Recall | Without notes, write everything you remember about each topic: terms, steps, examples, diagrams. | 10–15 min |
| 3. Check and fix | Compare with your notes. Re-study each gap, close the notes, and recall it again. Add each gap to your question list. | 10–15 min |
| 4. Mixed quiz | 10–15 questions drawn from all earlier weeks, shuffled across topics. Check every answer. | 10 min |
| 5. Plan | Put the topics you missed into two short sessions this week, with a day for each. List questions for your teacher. | 5 min |
In the first week of term there are no earlier weeks to quiz, so give step 4's time to step 3. From week two on, step 4 draws on every earlier week, so topics from week one keep coming back all term without extra planning. By the exam, you've already retrieved them many times on spaced days.
How to adjust it by subject
- Math, physics, chemistry: in step 4, redo one or two problems from each earlier week with the worked examples closed.
- Biology, history, psychology: in step 2, add one diagram or timeline drawn from memory.
- Languages: in step 2, say or write five full sentences using the week's vocabulary, then check them.
- Literature, philosophy, law: in step 2, state each reading's main argument in two sentences without looking.
How to make the habit stick
Tie it to something you already do with an if-then plan: "After Sunday lunch, I sit at my desk and start the weekly review." A meta-analysis of 94 tests found that plans like this had a medium-to-large effect on actually following through. If 45 minutes feels like too much, start with 20 minutes (steps 2 and 4 only) and build up. When you miss the slot, move it to a named backup time the same weekend rather than skipping the week. Our guide to building a study routine covers how to choose the anchor.
How to make a revision timetable
Work backward from your first exam. Here's a four-week timetable for three subjects, with about two to three hours of revision a day.
| Weeks before exam | Focus | What a day looks like |
|---|---|---|
| 4 | Finish learning and build your question lists | Two subjects a day: blank-page recall per topic, then turn gaps into flashcards and questions |
| 3 | Practice questions and spaced recall | Three subjects a day in 45-minute blocks; each block starts with five minutes of recall on an older topic |
| 2 | Past papers and mixed practice | One timed past paper (or section) a day, rotating subjects; mark it and redo every error |
| 1 | Exam conditions and weak spots only | Full timed papers, then targeted review of repeated mistakes. Stop new material two days out. Keep your normal sleep. |
A few rules that keep a timetable realistic:
- Mix subjects within each day. Two or three subjects a day give you built-in spacing and stop one subject from swallowing the week.
- Plan specific tasks, not subjects. "Chemistry: 2019 Paper 1, questions 1–10" beats "Chemistry, 2 hours".
- Leave one block a day empty. Something will overrun.
- Check progress weekly. If past paper scores in one subject aren't moving, move time toward it.
For a fuller countdown, including the night before and the morning of the exam, see how to prepare for exams.
Frequently asked questions
What is the best way to revise?
Self-testing spread over time. Read the material once, then revise by answering questions from memory, doing past papers, or writing everything you remember on a blank page, and check your answers each time. Come back to each topic several times with gaps of a few days, and mix topics within sessions. Practice testing and spaced practice are the two techniques with the strongest research support.
How do you review for a test effectively?
Start several days before the test. List every topic, test yourself on each one with recall or practice questions, and spend most of your time on what you got wrong. Two or three days before, do a timed practice test in the real format. The night before, do a short review of your weakest items and go to bed at your usual time.
How long should I revise each day?
It depends on how close your exams are, but quality matters more than hours. Two to three hours of active revision a day, split into 30- to 50-minute blocks with breaks, is plenty for most students four weeks out. If you find yourself rereading or drifting, end the block and switch to practice questions or a different subject.
What is a weekly review for students?
A weekly review is a fixed session, usually 30 to 60 minutes, where you recall the week's material from memory, check it against your notes, quiz yourself on earlier weeks, and plan the next week's study around the gaps. It spreads revision across the whole term, so exam preparation becomes practice rather than relearning.
How far in advance should I start revising?
For major exams, start about four weeks before for each subject, earlier if you have many exams close together. For a single unit test, four or five days is usually enough. If you run a weekly review during the term, you'll need less time at the end, because you won't be relearning material you've already forgotten.
Is it better to revise in the morning or at night?
Pick the time you can protect consistently and that doesn't cut into sleep. Both can work. Morning sessions suit people who are alert early; evening sessions are fine as long as you still get a full night's sleep. Our guide to studying in the morning vs at night looks at the evidence.
Sources and further reading
Start with the primary research and official guidance below. Links open in a new tab so you can compare the evidence with the article.
- Read source
Test-enhanced learning: Taking memory tests improves long-term retention
Roediger & Karpicke, Psychological Science, 2006
- Read source
Metacognitive strategies in student learning: Do students practise retrieval when they study on their own?
Karpicke, Butler & Roediger, Memory, 2009
- Read source
Improving students' learning with effective learning techniques
Dunlosky et al., Psychological Science in the Public Interest, 2013
- Read source
The shuffling of mathematics problems improves learning
Rohrer & Taylor, Instructional Science, 2007
- Read source
Spacing effects in learning: a temporal ridgeline of optimal retention
Cepeda, Vul, Rohrer, Wixted & Pashler, Psychological Science, 2008
- Read source
Study strategies of college students: are self-testing and scheduling related to achievement?
Hartwig & Dunlosky, Psychonomic Bulletin & Review, 2012
- Read source
Implementation intentions and goal achievement: A meta-analysis of effects and processes
Gollwitzer & Sheeran, Advances in Experimental Social Psychology, 2006