Retrieval Practice: How to Study for IELTS

Testing yourself usually helps you remember more than reading the same pages again. Researchers call this retrieval practice, or the testing effect. This guide explains what the studies found and how to use it when you study for IELTS.

What retrieval practice is

Retrieval practice means pulling an answer out of your memory. You close the book, write what you remember, then check. A practice test is one example. Flashcards are another, according to a 2013 review of study methods by Dunlosky and colleagues.

Rereading is the opposite, because the answer is in front of you. The same review rated rereading, highlighting and summarising as low utility. It rated practice testing and spacing as high utility.

What the research shows

In a 2006 experiment by Roediger and Karpicke, 120 university students studied short passages. Some then read the passage again. Others took a free-recall test with no feedback. A week later, the tested group recalled 56% of the passage. The group that reread recalled 42%. The passages came from a TOEFL preparation book.

Timing mattered. Five minutes after studying, rereading gave better recall, 81% against 75%. Testing pulled ahead after 2 days and after 1 week. So the benefit of testing showed up on later tests, not on a test a few minutes later.

A 2014 review by Rowland combined many lab experiments that compared testing with restudying. In 81% of the results, testing did better. In 18%, restudying did better. The benefit was larger when the final test came a day or more later.

A 2021 review of classroom quizzing combined data from 222 studies and 48,478 students. It found a medium-sized boost to academic achievement. We read only the abstract of this review.

What makes it work better

Feedback matters. Rowland found the largest benefit when learners got feedback after the test. Without feedback, tests where students got half or fewer of the answers right gave no reliable benefit. The 2013 review by Dunlosky and colleagues called the advantage of testing with feedback over restudying extremely robust.

The format matters too. In Rowland's review, tests that make you produce an answer did better than tests that only ask you to recognise one. A US government practice guide agrees. It suggests closed-book quizzes and correct-answer feedback.

The forward testing effect

Testing can also help you learn new material that comes after the test. This is the forward testing effect. A 2018 review by Yang, Potts and Shanks describes it this way: interim testing of studied information "facilitates learning and retrieval of new information".

Two studies in that review show it. In a word-list experiment, people tested after each list recalled about twice as many words from the last list. The comparison groups did maths problems or restudied.

In the second study, people read a text in sections. Those tested after each section recalled about twice as much of the third section as people with no tests in between.

There are limits. The review says interim testing can lead to negative effects in some situations. One study found the effect in adults and older children but not in younger children. Testing the effect in classrooms was still a priority for future research when the review was written.

Spacing: when to practise again

Spacing means splitting practice across several days instead of doing it all at once. A 2006 review by Cepeda and colleagues covered 839 assessments in 317 experiments. It found that the best gap between sessions grows as the time you need to remember grows. It covered verbal memory tasks only.

A 2008 online experiment had 1,354 people learn trivia facts. They reviewed the facts after a gap, then took a test 7 to 350 days after the review. The best gap was about 20% to 40% of the delay for a one-week test. It fell to about 5% to 10% for a one-year test.

Of the gaps tried, the best was 11 days when the test came 35 days after the review. It was 21 days when the test came 70 days after. This was trivia, so treat the numbers as a guide and not a rule.

If you are unsure, leave a longer gap. The US practice guide says a gap that is too long costs much less than a gap that is too short.

The forgetting curve

Memory fades with time. In a 2015 replication of Ebbinghaus's classic experiment, one person learned lists of nonsense syllables. They were tested at gaps of up to 31 days. The authors concluded that the forgetting curve was replicated. One person and nonsense syllables cannot tell you how fast you forget IELTS vocabulary.

Interleaving: mixing question types

Interleaving means mixing different kinds of problems in one session. Blocking means practising one kind at a time.

In a small study by Rohrer and Taylor, 18 students learned to find the volume of four solids. A week later, the students who mixed problem types scored 63%. The students who practised one type at a time scored 20%. Mixing was harder during practice. During practice, the blocked group scored 89% and the mixed group scored 60%.

The evidence is thinner outside maths. The 2013 review by Dunlosky and colleagues rated interleaving as moderate utility. It said it did not appear that interleaved practice of vocabulary boosts retention. Its advice was to practise a new kind of problem on its own first, then mix it with earlier kinds.

What the studies do not show

• No study here tested IELTS tasks. They tested recall of word lists, nonsense syllables, facts and passages, classroom quizzing, and one maths task.
• Most participants were university students. The 2014 review left classroom studies out.
• Testing does not win every time. In 18% of the results in the 2014 review, restudying did better.
• The 2006 authors wrote that the limits of the testing effect were not yet known.

None of this shows that retrieval practice raises an IELTS band. It shows that testing, especially with feedback, beat rereading for later recall in the testing studies.

How to use practice tests this way

This part is our advice, based on the studies above.

1. Test first, then check. Do a section under real time limits with no notes. Then mark it with the answer key.
2. Review every mistake. Write down why you lost the mark. Testing worked best with feedback in the 2014 review.
3. Come back to weak spots. Redo similar questions after a few days. Repeat again after a week or two. The studies give no IELTS schedule, so adjust to your test date.
4. Write from memory. For vocabulary and rules, write what you remember before you look at the list.
5. Mix once a type is familiar. Learn one question type on its own, then mix it with others. Do not expect mixing to help vocabulary learning.

You can find the free official practice tests in How to prepare for IELTS. How long to prepare for IELTS helps you plan the weeks. The IELTS Study Planner turns your test date into a weekly plan. If your scores have stopped rising, read why you can get stuck at band 6.5.

How we checked this

We read each study or review at its DOI link or a copy of the article. We last checked them on 24 October 2026. For the 2021 classroom review we read only the abstract. We use only what each source says. We do not say how much any method improves an IELTS score.

Frequently asked questions

Is retrieval practice the same as taking a practice test?

No. A practice test is one form of it. Flashcards and writing what you remember are others. The research covers all of these.

Is rereading useless?

No. Five minutes after studying, rereading gave better recall than testing in the 2006 experiment. After 2 days and after a week, testing did better. A large review rated rereading as low utility.

How early should I start?

Our advice: start early enough to see each topic at least twice. The studies do not give an IELTS schedule. Our advice is to use the study planner and leave gaps between sessions.

Will retrieval practice raise my IELTS band?

No study has tested that. The research shows better recall of studied material. It does not measure band scores.