L·03
Learning & Memory
Interleaving
Mixing problem types during practice feels worse and performs better than doing them in blocks.
- Evidence
- proven
- Topic
- Learning
- Things to do
- 3
- Read
- 1 min
provenHow strong is the evidence?
Tested again and again, by different people, and it keeps coming out the same. You can lean on this.
- Rohrer & Taylor, 2007
- Rohrer, Dedrick & Stershic, 2015 — 25% vs 80% on delayed test
Why it works
Blocked practice lets you apply the same method without deciding which method applies. In reality, choosing the method is the hard part.
What to do about it
- Shuffle the practice set so you must identify the type before solving.
- Rotate between two or three related skills within one session rather than one per session.
- Accept a worse session. Interleaved practice reliably feels like it is going badly.
Where people go wrong
Judging a practice method by how smooth it felt. Smoothness and learning are close to uncorrelated.
Read next
- Retrieval Beats ReviewTrying to recall something strengthens memory far more than reading it again. Rereading mostly builds confidence.proven
- SpacingThe same total study time, spread out, produces far more durable memory than massed together.proven
- Guess Before You're ToldAttempting an answer before learning it improves later retention — even when the guess is wrong.solid
- Ask Why It's TrueAsking “why would that be the case?” while reading beats any amount of summarising.solid