Worth knowing Learning

Mix your practice up instead of doing blocks

Practising one thing until you have it produces sessions that feel great and skills that vanish.

Moderate evidenceReal support, but smaller effects or fewer replications than you would want.
What it costs Same time, worse sessions

Do this

Alternate between related problem types or skills within a session rather than completing all of one before the next. Randomise the order where you can. Accept that your in-session performance will look worse.

Why it works

Interleaving forces you to work out which approach applies, which is the actual skill you need later - blocked practice removes that step because the answer type is given by the context. Studies in maths, sport and category learning show worse practice performance and better retention and transfer.

Where it fails

Requires enough baseline competence that you are not just failing at everything. Advantages are clearest for related-but-confusable material; interleaving unrelated things does little. Learners consistently rate it as less effective, so it is hard to stick with.

How you’ll know

Compare a delayed test, not a session. Judging by how the session felt will point you the wrong way every time.