Interleaving is when teachers teach several topics at the same time, rather than teaching a single topic in one block. This means pupils have to switch their attention between two or more topics, which should lead to better retention.
The approach is often confused with spaced practice, but there is a key difference: interleaving involves teaching similar topics at the same time, while spaced practice can involve swapping between unrelated topics.
How does it work in the classroom?
In a Tes column, Mark Enser, head of geography at Ofsted and former teacher, explains that there are misconceptions in the classroom around interleaving. For example, he says, many assume interleaving simply involves swapping between topics. Rather than teaching a unit on tectonics in a block, for instance, teachers break that up by “teaching a lesson on tectonics, the next on rivers, and then one on urbanisation, before returning to tectonics”.
Enser, however, questions the effectiveness of this approach; he argues that pupils “will have too long a break between their first and second lessons on tectonics”, leading to confusion and a “very fragmented curriculum”. A better option, he suggests, is to “interweave” content, by identifying themes and concepts that recur throughout different topics.
Evidence isn’t there to support these interpretations - as previously mentioned, most of the research has been conducted in maths, and not subjects like geography. But in the EEF’s guidance document, Cognitive Science Approaches in the Classroom, the following evidence-based example is provided.
“When teaching fractions to his class, Mr Hodiak likes to test his pupils as this can help to identify areas for improvement and gaps in understanding. To ensure that his pupils have to think hard about how to solve fractions, Mr Hodiak interleaves problems with different numerators and denominators. Mr Hodiak thinks that by requiring his pupils to identify the subtle differences between these varied types of problems, he can embed learning and improve pupils’ ability to select appropriate strategies when solving fractions in the future.”
The Education Endowment Foundation (EEF) is an independent charity dedicated to breaking the link between family income and educational achievement.
To achieve this, it summarises the best available evidence for teachers; its Teaching and Learning Toolkit, for example, is used by 70 per cent of secondary schools.
The charity also generates new evidence of “what works” to improve teaching and learning, by funding independent evaluations of high-potential projects, and supports teachers and senior leaders to use the evidence to achieve the maximum possible benefit for young people.
