Mixed practice

Interleaving

Mix topics in one session — don’t block them.

What the Research Says

Most students revise by blocking — an hour on the Elizabethan Age, an hour on Germany, an hour on Crime & Punishment. It feels productive and the topic seems clear by the end. Interleaving is the opposite: you jump between topics inside a single session. It feels worse at the time, and you’ll make more mistakes. But when the real exam arrives, you will be dramatically better at knowing which second-order concept a question is targeting — cause, consequence, significance, change — and that identification is often the hardest part of a History response.

Evidence Base

Study	Finding	Impact
Rohrer & Taylor (2007)	Students who interleaved topics scored 43% higher on delayed tests than blocked-practice students.	Same time spent — huge difference in exam performance.
Birnbaum et al. (2013)	Interleaved learners felt LESS confident during practice but performed BETTER in the test.	If revision feels too easy, interleave.
Bjork & Bjork (2011)	Desirable difficulties — including interleaving — create durable long-term learning at the cost of short-term performance.	Short-term struggle is the price of long-term gain.
Taylor & Rohrer (2010)	Benefit was largest when topics looked superficially similar — students learnt to DISTINGUISH them.	Most useful where students confuse related ideas — exactly the problem with second-order concepts.

Step-by-Step Method

1
Pick 3–5 related topics or question types — topics that share a paper, a second-order concept, or a question format. Similar enough that students confuse them.
2
Make a mixed problem set — 10–15 questions drawn from all the topics. Don’t label which topic each question belongs to.
3
Attempt each question cold — the first step is identifying what’s being asked. Is this a cause question, a significance question, or a change-and-continuity question? That identification is the skill you’re training.
4
Mark after every question — note which concept or topic area each question targeted. Pay attention to mis-identifications — those are the highest-value gaps.
5
Rebuild a new mixed set tomorrow — same topics, different questions, different order. Over time, misclassifications drop.
6
Expect to feel worse than blocked practice — that’s the right feeling. Your exam self will thank you.

Example 1 — Mixing depth-study and thematic-study question types

Mix questions from your British depth study, your period study and your thematic study in one 40-minute session. Write 12 questions on separate slips: four from each area, shuffled. Before each question, ask yourself: “Is this a cause/consequence question, a significance question, a source utility question, or a change/continuity question?” Students regularly confuse a 6-mark ‘explain a cause’ question (which wants developed causation) with an 8-mark ‘explain the significance of’ question (which wants a judgement about lasting impact). The interleaving drill trains that distinction directly, preventing the common error of writing a narrative response to a significance question.

Example 2 — Mixing content from across the three thematic eras

For a thematic study such as Crime & Punishment or Warfare, mix questions from the medieval (c.500–1500), early modern (c.1500–1750) and modern (c.1750–present) eras in one session without labelling which era each question comes from. This trains you to recognise which era the evidence belongs to and whether it represents change or continuity — the exact discrimination the thematic essay demands. Students who revise each era in isolation often produce essays that list events chronologically instead of weighing change against continuity across all three periods. Interleaving prevents this by making era-to-era comparison the natural reflex.

Common Pitfalls

Interleaving before you know the basics. You need to know each topic individually first. Use interleaving once you’ve studied all your options — not as a first-pass strategy.
Giving up because it feels hard. Difficulty during interleaved practice is the signal it’s working. Persist.
Mixing completely unrelated subjects. Interleaving works best when the topics are related enough to be confused. Mix History question types together — not History with Geography.
Not checking mis-identifications. The mistake is the data. If you approached a ‘why do interpretations differ?’ question as if it were a ‘describe a feature’ question, that confusion is exactly what needs fixing before the exam.

When to Use This

Start interleaving once you have studied all your options at least once. In the final six weeks before the exam, replace most blocked revision with interleaved mixed sets. Particularly powerful the week before the exam when you want to simulate the unpredictable order in which questions appear — the exam will not group all the causation questions together, and neither should your revision.