Desirable difficulties are supposedly the learning sweet spot that can boost development – but what does the wider education research say about them, and how can they be harnessed by teachers?
“Desirable difficulties” is a term coined in 1994 by cognitive psychologist Robert A Bjork - who, alongside his wife Elizabeth, leads the Bjork Learning and Forgetting Lab at the University of California, Los Angeles - to refer to tasks that require a level of effort that will improve long-term performance.
The concept proposes that the mind acts like a muscle, which will grow more if it is worked harder. The key, Bjork proposed, is to find the sweet spot of challenge: so just as lifting a light weight won’t build much muscle mass, undertaking tasks that don’t require a lot of thinking won’t encourage mental development.
According to Nate Kornell, a former graduate student of Bjork’s, who has gone on to become a leading expert on the topic, desirable difficulties are “any kind of educational intervention that causes students to do worse in the short term but better in the long term”, as “when you have to process information, when you have to think hard about it, it gets encoded better”.
How does it work in the classroom?
In the classroom, desirable difficulties often encompass:
Spacing (leaving gaps between multiple study sessions).
Interleaving (spacing study by chopping it into blocks on related but distinct topics, which are interspersed).
Testing oneself.
Generating one’s own answers (rather than having them provided).
Speaking to Tes, Kornell explained why such approaches are so successful.
Spacing between study sessions allows the developing brain to “consolidate the information that you’ve been learning, but also to forget some stuff”, which then requires your brain to re-encode this information, which is valuable, he said.
And in testing oneself, the benefit is all about “trying to make a retrieval attempt”, and to probe your memory to see if there’s something there, which creates “a fertile ground for the information that you’re being tested on to be encoded”.
He also stated that it’s important to highlight that mistakes are a key part of desirable difficulty, and that they should be presented as such, rather than as a failure.
Kornell continued: “When a kid is struggling with something and they finally get it right, take a second to remind them: ‘Hey, remember how much you struggled with this? Now you get this and notice that your struggle paid off.’”
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.
