How to Review Lecture Notes (A 20-Minute Routine)

Most students take notes and never look at them again until exam week, when they have forgotten much of the lecture and are not sure what the notes meant. A short review soon after each lecture can change this completely. Twenty minutes within a day does more for memory than hours of rereading a month later.

This guide gives you a simple routine that you can repeat after every lecture, plus a weekly and exam-time version.

Why reviewing soon matters

Memory fades fast after learning, and most of the loss happens in the first day or two. Reviewing soon, while you still remember the context, catches the material before it slips away. You can also fix gaps while you can still tell what you meant. A cryptic note you cannot decode three weeks later was probably clear the evening of the lecture.

Spacing then does the rest: later reviews at growing intervals keep the memory from fading again.

The first review: 15 to 20 minutes

Here is how to spend the time.

Minutes 0 to 5: read and repair. Read the notes from top to bottom. Complete sentences you cut short, spell out abbreviations you will not remember and clarify messy handwriting. Mark anything confusing with a question mark.

Minutes 5 to 10: fill gaps. Use the slides, the textbook or a classmate's notes to fill the gaps. Add what you missed, in a different color so you can see what you added.

Minutes 10 to 14: summarize and question. Write a short summary in your own words without looking. Then turn headings, definitions and examples into questions.

Minutes 14 to 20: test yourself. Cover your notes and try to answer the questions. Check and mark what you missed.

What to add to your notes

A good set of notes after review has:

• the date, course and lecture topic at the top;
• the main points, structured clearly;
• examples next to the ideas they illustrate;
• a summary of two or three sentences;
• questions in the margin or on a cue column;
• a list of things to ask the instructor;
• links to related lectures or textbook sections.

Our guide to note-taking methods shows layouts such as Cornell that build most of this in.

The weekly review

Once a week, spend 30 to 45 minutes on all of the week's notes together:

1. Read your summaries for the week, one after another.
2. Test yourself on the questions from every lecture.
3. Draw links between lectures, showing how this week's ideas connect.
4. List anything still unclear, and book office hours or send an email.
5. Add key facts to flashcards if you use them.
6. Plan next week's reading and see what it builds on.

This session is also an easy place to catch topics you are drifting on before they become problems.

The exam review

In the weeks before an exam, your notes become the source for practice:

• turn summaries into a one-page overview of each topic;
• answer your question lists from memory, mixing topics;
• use past papers to see how topics are examined;
• focus on the questions you missed repeatedly;
• stop rereading complete notes, and test yourself on them instead.

Because you reviewed regularly, exam review is mostly testing and not relearning.

Ways to make reviewing stick

• Review at the same time each day, such as right after your last class or before dinner.
• Do it in the same place, so it becomes a habit.
• Keep it short, since a 15-minute routine you do is better than an hour you skip.
• Pair it with something pleasant, like a coffee.
• Track it, by ticking off each lecture reviewed.

When notes are poor

If your notes are thin, confused or missing, do not just review them. Rebuild them:

1. Read the textbook section on the topic.
2. Fill in the main ideas in your own words.
3. Compare with a classmate's notes or lecture slides.
4. Write questions and summaries as above.

If this happens regularly, change how you take notes during lectures. Our guide to taking notes in class covers preparing, listening for structure and keeping up.

Reviewing digital notes

Digital notes make review quick if you organize them. Keep one file or page per lecture, with consistent titles, and use headings and bold text for key terms. Use the search function to find topics, and consider turning questions into flashcards in an app. Do not let digital notes become a giant unsorted pile, which is as hard to review as a stack of loose paper.

A sample week of reviewing

Here is how the routine might look for a student with three lectures on Monday, Wednesday and Friday:

• Monday evening: 15 minutes on each of Monday's lectures, with summaries and questions.
• Tuesday: a five-minute check on Monday's notes, answering the questions from memory.
• Wednesday evening: a 15-minute review of Wednesday's lecture.
• Thursday: quick recall of Monday and Wednesday's questions.
• Friday evening: the Friday review, followed by a 40-minute weekly session across all three lectures.
• Weekend: a short test of the week's questions, and a plan for next week.

Notice that the day after each lecture includes a brief recall check, which is cheap and works as a second spaced review.

Reviewing notes in a group

Two or three classmates can review together, if they stay focused. Each person brings their notes and one set of questions. Take turns answering from memory, then compare notes to see what was missed. Do it for 30 minutes, once a week, and keep a list of questions to take to the instructor. A group review also exposes different ways of understanding the same lecture, which can clear up confusion quickly.

Reviewing when you are behind

If you have fallen behind, do not try to catch up on every lecture at once. Review the most recent lecture first, since it is freshest and likely to build on earlier ones. Then work back, doing shorter reviews of older lectures, with a focus on topics that will be tested soon. Ask a classmate for their summaries for the lectures you missed. A smaller routine you can keep up beats a heroic catch-up that you drop after two days.

Common mistakes

1. Waiting until exam week.
2. Rereading instead of testing.
3. Copying notes neatly, with no thinking.
4. Skipping summaries and questions.
5. Reviewing for too long, then quitting the habit.
6. Ignoring the parts you do not understand.

A note for students with limited time

If you work, commute or care for family, a 20-minute review after every lecture may be unrealistic. A shorter version still helps: five minutes on the commute reading the summary line and one question, and a single longer session at the weekend. Even a two-minute recall of three key points, done on the bus, uses the same principle. Doing a little regularly matters much more than doing a lot occasionally.

The bottom line

Review within a day, keep it short and make it active: repair, summarize, question and test. Add a weekly review and an exam-time review, and your notes will work for you instead of sitting unused.