It is important to do varied and challenging practice tasks when learning to drive or learning a sport, even though these may lead to errors. In a similar way, scientific research has established a set of ‘desirable difficulties’ that apply to classroom teaching — factors which make learning more challenging and error-prone, but also more effective in the long run. Desirable difficulties can make progress feel slower to the learner, but they are beneficial in building knowledge that lasts and which can be used in multiple situations. Two of the most useful desirable difficulties for teachers to know about are the spacing effect and retrieval practice.
The spacing effect
The spacing effect means that a re-study activity will be more effective after a delay than it would be if it were done sooner or immediately. Revision tasks that are spaced out over time may remind learners of their earlier learning that has been partially forgotten, and are also more challenging. These features can lead to more effective learning — counterintuitively, a degree of forgetting appears to help the learning process over the long term.
The advantages of spacing should make us rethink the idea that information can be learned in a single lesson. Instead, each lesson can be seen as part of a longer process of building usable knowledge.
Applying the spacing effect
One of the appealing factors about the spacing effect is that it is not burdensome to implement. Classroom materials and tasks don’t need to change at all. Instead of consolidating the learning of a new concept at the end of a lesson you could do this at the start of the next lesson instead, perhaps with an introduction and some pre-questioning the lesson before. This would space the learning over three lessons rather than one, without being any more complex to teach. With this technique, the timing of each task starts to be seen as a crucial professional decision.
Another desirable difficulty involves prompting learners to retrieve information from long-term memory. This is known as retrieval practice. For example, a class of learners may hear an explanation and then be asked to write notes on what they can remember, or to answer a quiz. This contrasts with more passive activities such as copying directly from a textbook or screen, re-reading notes, or highlighting texts.
Retrieval practice is consistently found to be superior to other forms of learning and revising. Like spacing, the technique can feel harder to students, but the process of effortfully bringing information back to mind seems to consolidate new learning. The learner is also developing their ability to use the information in context — something that they will later need to do in an exam, or in real-world situations.
Applying retrieval practice
Retrieval practice can be built into lessons via a variety of types of task. The most obvious example is to set low-stakes quizzes, but a discussion will also prompt retrieval from memory, as will writing a closed-book summary. In short, anything that requires a learner to actively retrieve what they have previously seen or studied can be beneficial.
Students can also use the principle of retrieval practice when revising. Rather than re-reading or highlighting, it will be better for them to test themselves using books, flashcards, or apps like Quizlet. This can also help them to recognise gaps in their learning, as some may believe that they know a topic well just because it looks familiar; researchers call this an illusion of competence. Quizzes help to shatter this illusion, providing valuable feedback on what the student needs to practice further.
About our author: Jonathan Firth has taught psychology at secondary school level for nearly twenty years, and now works in teacher education at the University of Strathclyde. He has written school books for both Collins Education and Leckie, as well both writing on and conducting research into evidence-based teaching practice. Follow him on Twitter – @JW_Firth