Mix your practice
Shuffling different kinds of problems feels harder, and teaches more.
PsychologyHow to studyAbout 3 min: 2 reading, 1 practiceUpdated
Educational, not medical or mental-health advice.
- Tell blocked from interleaved practice
- Explain why mixing helps in exams
- Know when a short block is still fine
How to study: lesson 3 of 5
- How to study
- Test yourself instead of rereading 3 min
- Space it out 3 min
- Mix your practice 3 min
- Focus in short sessions 3 min
- Make a study plan you will keep 4 min
Try first
You haven't learned this yet, so guess. Guessing before you read helps the explanation stick. Nothing here is scored.
Already know this? Take a 3-question check and skip ahead.
Get all three right and the lesson is marked done.
Pairs with Rohrer & Taylor (2007), "The shuffling of mathematics problems improves learning"; Dunlosky et al. (2013)
What it is
Blocked practice means doing ten problems of one kind, then ten of the next. Interleaved practice mixes them: one of each kind, shuffled, so you never know which kind is coming.
Interleaving forces you to work out which method a problem needs before you use it. On an exam, that choice is usually half the job.
Quick check
Tap an answer to check it.
You practise A, B, C, A, C, B in a random order. What is this called?
- Blocked means all of one type first
Show answer
Interleaved practice. Mixing types in a random order is interleaving.
Why it matters
In a study by Rohrer and Taylor (2007), students practised maths problems either in blocks or shuffled. The blocked group did better during practice. A week later, on the test, the shuffled group did much better.
That is the catch: interleaving feels slower and more frustrating, so learners often think it is not working. The Dunlosky review (2013) rated it as promising, with more research needed outside maths.
Worked example
You are revising finance with three lesson quizzes: compound interest, present value and inflation.
- Blocked: all the compound interest questions, then all the present value ones, then all the inflation ones.
- Interleaved: one compound interest, one inflation, one present value, one compound interest, and so on, in random order.
The timed practice on each subject's exam-prep page already shuffles questions from every lesson, so it interleaves for you.
Common mistake
Mixing before you know the basics. Interleave once you have met each type of problem at least once. On day one of something brand new, a short block of practice is fine.
Key terms
- blocked practice
- doing many problems of one type in a row
- interleaved practice
- mixing different types of problem in a random order
Practise the key terms
Tap a card to turn it over. 2 cards.
| Front | Back |
|---|---|
| blocked practice | doing many problems of one type in a row |
| interleaved practice | mixing different types of problem in a random order |
Practice
Quick quiz
Tap an answer to check it.
In Rohrer and Taylor's study, which group did better on the test a week later?
- Blocked looked better during practice, not on the test
Show answer
The shuffled (interleaved) group. Blocked practice looked better during practice, but interleaved practice won on the test.
What does interleaving train that blocked practice does not?
- Mixing isn't about speed
- It is about practice problems, not reading
Show answer
Choosing which method a problem needs. When problems are mixed, you have to recognise the type each time.
In short
- Interleaving mixes problem types, so you must choose the method each time.
- It feels harder and scores lower during practice, but wins on the later test (Rohrer & Taylor, 2007).
- Use it once you have met each type at least once.
- Studyfern's timed practice already shuffles questions for you.
Mastery check
Answer without looking back. Score 80% or more and the lesson is marked done. Your result is kept only in this browser.
Check yourself
Answer in your head first, then open the answer. Nothing is saved.
What is the difference between blocked and interleaved practice?
Show answer
Blocked does one type of problem at a time; interleaved mixes different types together.
Why do learners often think interleaving is not working?
Show answer
It feels harder and scores lower during practice, even though it leads to better results later.
When is a short block of one type still fine?
Show answer
When the topic is brand new and you are meeting that kind of problem for the first time.
Further reading
- Rohrer, D., & Taylor, K. (2007). The shuffling of mathematics problems improves learning. Instructional Science, 35, 481–498.
- Dunlosky et al. (2013), as in the first lesson of this path.
Finished? Mark it done to fill in your leaf on the Psychology map.