How to Study from Lecture Recordings: A Method That Beats Rewatching

Recorded lectures were once a convenience for students who were ill. In many universities they are now standard, and some courses are taught mainly through recordings. That has made one problem very common: the recordings pile up, because there is always a later moment to watch them, and when exam season arrives students try to work through ten or twenty hours of video.

A recording is a useful resource. You can pause it, replay a difficult explanation and watch when you are alert. But watching a video is not the same as learning from it, and watching it twice is rarely twice as useful. This guide sets out a way of using recordings that keeps the advantages and avoids the slow, passive rewatching that takes up so much exam preparation time.

Why rewatching lectures feels useful but rarely is

Question: If you understood the lecture while watching it, why do you not remember it a week later?

Answer: Because understanding an explanation while someone gives it is different from being able to reproduce it. Watching a lecture is a form of rereading: the information is presented to you and it feels clear. The 2013 review of study techniques by Dunlosky and colleagues rated rereading as low utility and practice testing as high utility. The same reasoning applies to video. The guide on why rereading notes is ineffective explains the effect in more detail.

Recordings add a second problem: attention. At home, with a laptop and a phone nearby, it is easy to let a lecture run while your mind is elsewhere. A 2013 study by Szpunar, Khan and Schacter found that inserting short tests between segments of a video lecture reduced mind wandering, increased note taking and improved performance on a final test compared with watching without those tests. You can apply the same idea yourself by pausing to recall at regular intervals.

Live lectures, recordings and slides: what each is good for

Recordings work best when they are one part of a set of resources, each used for what it does well.

The pattern is that recordings are strongest at the beginning, when you first meet the material, and as a reference for specific gaps later. They are weakest as a revision tool in their own right.

How to study from lecture recordings, step by step

The method below takes slightly longer than the recording itself on the first pass, and saves far more time later because you will not need to watch the lecture again.

1. Schedule recordings like lectures. Pick a fixed slot each week for each module, ideally within a day or two of the original lecture. Recordings that have no time attached to them are the ones that pile up.
2. Preview the slides for five minutes. Look at the headings and diagrams so you know the structure before you press play. This makes it easier to notice which parts of the talk explain which slides.
3. Watch in segments. Stop every 10 to 15 minutes, or at each natural break in the topic.
4. Recall before you take notes. At each pause, look away from the screen and write down the main points of the segment from memory. Then check the slides and add what you missed. This is the step that makes the biggest difference.
5. Add timestamps to anything unclear. Write the time next to explanations you did not follow or examples you want to come back to. Later you can jump straight to that point instead of searching.
6. Finish with a one-paragraph summary. Without looking, write what the lecture was about and how its parts connect. If you cannot, note which part is missing.
7. Turn notes into questions within 24 hours. Write a short list of questions the lecture should allow you to answer. These become your material for review in the following weeks.

Many of the principles that apply to live lectures still apply here, such as writing in your own words and recording examples rather than every sentence. The guide on taking lecture notes covers those in detail.

Should you watch lecture recordings at a faster speed?

Question: Is it fine to watch at 1.5x or 2x to save time?

Answer: It depends on the material. A lecturer who speaks slowly, or a lecture that reviews content you already know, can often be followed at a moderately higher speed. Dense material is different. Derivations, proofs, new terminology and detailed diagrams need time to process, and speeding them up mostly means you pause more often or miss the point.

A useful rule is to judge speed by the recall pauses. If you can write down the main points of each segment at the faster speed, the speed is fine. If your recall is thin, slow down. Saving twenty minutes on playback is not a gain if you need to rewatch the lecture later.

How do you catch up when recordings have piled up?

If you are several weeks behind, watching everything in order at normal speed is rarely realistic. Triage instead.

• Go through the slides for every missed lecture first. This takes a fraction of the time and shows you what each lecture covers.
• Rank the lectures by how much they matter for the exam, using the module description, past papers and anything the lecturer has said about exam content.
• Watch the top-ranked lectures properly, using the segment and recall method above.
• For the rest, study from the slides and watch only the sections where the slides do not explain enough on their own.
• Keep up with new lectures at the same time, so the backlog does not grow while you clear it.

For a broader plan that covers readings, assignments and lectures together, see how to catch up on university work.

What should you do with your notes after the recording?

Question: Once a recording is finished, how do you make sure the content is still there at exam time?

Answer: Review it through testing, spread over time. Answer the questions you wrote after the lecture a day later, then again a few days later, then again the following week. A 2006 meta-analysis by Cepeda and colleagues found that spacing study sessions apart produced better long-term retention than massing the same amount of study into one session.

This is where the slides become more useful than the video. They are quick to scan and easy to convert into questions, while the recording stays in the background for the occasional gap. The guide to studying from lecture slides explains that conversion step, and the guide to spaced repetition explains how to time the reviews.

FAQ: Studying from lecture recordings