How to Study Effectively: What the Research Says Works

To study effectively, test yourself instead of rereading, spread your sessions over days instead of cramming, and mix different kinds of problems together instead of doing one type at a time. Those three habits have the strongest evidence behind them. Highlighting, rereading and summarizing feel productive, but research rates them low.

Most advice on this topic is a list of tips: find a quiet room, take breaks, drink water. That is fine, but it skips the part that matters most, which is what you do during the hour you sit down. This article is about that hour.

The short version: which techniques work

In 2013 a group of psychologists reviewed hundreds of studies on ten common study techniques and rated each one by how useful it is for students (Dunlosky et al., 2013). Their ratings:

Technique	What it is	Rating
Practice testing	Quizzing yourself, flashcards, old exams	High
Distributed practice	Spreading study over several days	High
Elaborative interrogation	Asking "why is this true?"	Moderate
Self-explanation	Explaining each step to yourself	Moderate
Interleaved practice	Mixing problem types in one session	Moderate
Summarization	Writing summaries of the text	Low
Highlighting	Marking the text	Low
Keyword mnemonic	Memory tricks for word pairs	Low
Imagery for text	Picturing what you read	Low
Rereading	Reading the material again	Low

The two "high" techniques are not the ones most students use. When college students were asked how they study, rereading came out on top, and over half named it as their main strategy (Karpicke, Butler & Roediger, 2009).

The rest of this article goes through the techniques that hold up, in the order you would use them.

1. Test yourself instead of rereading

This is the single biggest change most students can make. Close your notes, ask yourself a question, answer it from memory, then check.

It works because the exam asks you to produce answers, and rereading only trains you to recognize them. In one study, students who practiced recalling a passage remembered about 61% of it a week later; students who reread it remembered about 40% (Roediger & Karpicke, 2006).

Ways to do it:

• Write everything you remember about a topic on a blank page, then check what you missed.
• Turn each section of your notes into a question and answer it with the notes covered.
• Use flashcards, and say the answer before you flip.
• Do practice problems or old exams without the worked example open.

We wrote a full guide with a routine for one lecture: how to do active recall.

2. Spread it out

Three one-hour sessions on Monday, Wednesday and Saturday beat one three-hour session on Saturday, even though the total time is the same. Memory fades a little between sessions, and pulling it back each time is what makes it stick. This "spacing effect" is one of the most reliable findings in learning research, across hundreds of experiments (Cepeda et al., 2006).

In practice:

• Review a lecture the same day, again a day or two later, then about a week later.
• Make the gaps longer each time you get something right.
• Start each exam's review at least a week or two before it, not the night before.

If you have several exams, our free study schedule maker lays out the review days for each topic, counting back from your exam dates.

3. Mix problem types together

Textbooks usually give you twenty problems of the same kind in a row. That feels smooth, because you know which method to use before you read the question. The exam doesn't tell you which method to use.

Interleaving means shuffling problem types together, so each time you have to decide which approach fits. In one experiment, students practiced finding the volume of four kinds of shapes. Those who practiced the types mixed together scored 63% on a test a week later; those who practiced one type at a time scored 20% (Rohrer & Taylor, 2007). During practice, the mixed group did worse. On the test, they did far better.

In practice:

• After you learn a new method, mix its problems in with the last two or three chapters'.
• When you review, shuffle your flashcards across topics instead of going deck by deck.
• Old exams are already interleaved. Use them.

4. Ask "why?" and explain it to yourself

The two "moderate" techniques are cheap to add on top of testing:

• Elaborative interrogation: when you read a fact, ask why it is true. "Why does the cell membrane let water through but not ions?" If you can't answer, that's a gap.
• Self-explanation: when you follow a worked example, explain each step in your own words before you look at the next one. "Why did they divide both sides here?"

Both force you to connect the new idea to what you already know, which is what makes it usable later. Explaining a topic out loud, without notes, to a friend or an empty room does the same thing.

What doesn't work as well as it feels

• Rereading. It makes the material familiar, and familiar feels learned. It's fine for a first pass, not as your main way to review.
• Highlighting. Marking a line is not the same as being able to say what it means. If you highlight, turn each highlighted part into a question later.
• Summarizing. Useful if you are good at it and do it without looking. Copying the textbook in shorter words is mostly rereading.
• Studying to your "learning style". The idea that you learn better if material matches your style (visual, auditory, and so on) has not held up when it was tested properly (Pashler et al., 2008). Use whatever format fits the material: diagrams for anatomy, problems for physics.
• Long sessions with your phone on the desk. In one study, people did worse on attention and memory tasks when their phone was on the desk than when it was in another room, even when it was turned off (Ward et al., 2017). Put it in a bag or another room.

A weekly routine that puts it together

Here is what effective studying looks like for one class, in a normal week with two lectures:

1. After each lecture (15 minutes). Blank page: write what you remember. Check against the slides. Write a question next to each part you missed.
2. The next day (15 minutes). Answer those questions with the notes closed. Make flashcards for terms you keep missing.
3. Mid-week (20 minutes). Practice problems from this week, mixed with a few from earlier weeks.
4. Weekend (30 minutes). Flashcards across all topics so far, shuffled. Then one blank page for the whole week.

That is about an hour and a half a week per class, in short pieces, and every piece is either testing, spacing or mixing. Before an exam you add more of the same, not something new.

If your class gives you slides rather than a textbook, start here: how to study lecture slides. If an exam is coming up soon, see how to study for finals.

The basics still count

The tips in every other article on this topic are not wrong. They just come after the method:

• Sleep. Memory is consolidated during sleep. An all-nighter costs you more than the hours it buys.
• Short sessions with breaks. 25 to 50 minutes on one thing, then a short break, is easier to keep up than three hours straight. The exact number matters less than stopping before your attention is gone.
• One place, few distractions. Not because the room is magic, but because it removes decisions.

Questions students ask

What is the most effective way to study? Testing yourself on the material, spread over several days. Those two techniques have the strongest evidence of any study method.

How many hours a day should I study? There is no fixed number. Two short sessions of active recall usually beat four hours of rereading. Track what you can answer without notes, not how long you sat at the desk.

Is it better to study in the morning or at night? Whichever you can do consistently. What matters more is sleeping after you study, so don't trade sleep for late-night sessions.

Why do I forget everything I study? Usually because the studying was rereading, done once, close to the exam. Recognizing material while you read it doesn't mean you can recall it later. Test yourself, then test yourself again a few days later.

Does listening to music help you study? For most people, music with lyrics makes reading and writing tasks harder. If you want background sound, pick something without words, or nothing at all.