Active recall: what it is and how to use it

What it means

Active recall is testing yourself. You close the book and try to answer from memory, then check. Rereading, highlighting and watching a lecture again put information in front of you. Recall makes you bring it back yourself.

The evidence

In a 2006 study, Henry Roediger and Jeffrey Karpicke found that students who tested themselves remembered more a week later than students who reread the same passage, even though the rereaders felt more confident. This is known as the testing effect, and it has been repeated many times since.

Five ways to use it

• Blank page. After a chapter, write down all you remember on an empty page, then check against the book in a different colour.
• Questions, not notes. Write your notes as questions, and answer them later without looking.
• Flashcards. They suit reactions, formulas and Biology terms. Say the answer before you turn the card.
• Rework solved examples. For Physics and Maths, cover the solution and do it yourself. It's much harder than reading along.
• Explain it. Teach the idea to a friend, without notes.

Using it with spaced revision

Recall tells you how to review and spacing tells you when. They work best together. Use a spaced revision schedule for the dates, and recall on each of them.

Common mistakes

• Looking at the answer too soon. Give yourself a real attempt first.
• Keeping only the cards you already know. The wrong ones are where the learning is.
• Spending hours making beautiful notes or flashcards. Making them isn't the part that helps most.
• Recalling only once. It works best when you repeat it over days and weeks.