By Andy Tharby
Spaced practice (or ‘spacing’ or ‘distributed practice’) involves repeatedly coming back to the information that we are learning in various short sessions, spaced out over time, rather than ‘cramming’ it into a single intense period – known as ‘massed practice’. Unfortunately, massed practice is often our students’ study habit of choice and, just as unfortunately, many students hold the erroneous belief that it is superior to spaced practice.
Spaced practice means that we are given time to forget new information. We then have to work hard to remember this material which, in turn, helps to improve our future learning.
Along with retrieval practice, the effectiveness of spaced practice is supported by decades of strong research evidence from the US.
In his ultra-useful, ultra-accessible article on the effectiveness of popular study strategies, Professor John Dunlosky writes:
“Not using distributed practice for study is unfortunate, because the empirical evidence for the benefits of distributed (over massed) practice is overwhelming, and the strategy itself us relatively easy to understand and use. Even so, I suspect that many students will need to learn how to use it, especially for distributing practice across multiple sessions. The difficulty is simply that most students begin to prepare and study only when they are reminded that the next exam is tomorrow.”
In light of this, it is clear that spaced practice has important implications for how we plan the curriculum, plan lessons and help students to organise their revision for tests. The rest of the post is dedicated to examining two questions. First, how can teachers use spaced practice in their classrooms? Second, what are the potential pitfalls and mistakes to avoid when trying to implement spaced practice?
Putting spaced practice into practice
Careful curriculum design. To some extent, spaced practice is brought about naturally by the way that school timetables are organised. A student might have three history lessons a week: on a Monday morning, a Wednesday afternoon and a Thursday morning – a timetable which in itself creates a lot of useful spacing. However, an artfully designed subject curriculum can build on this effect very fruitfully. Important concepts should be spaced out across the curriculum and built upon over time. At secondary school, these can be introduced in Year 7 and then reinforced and extended upon as the students move through the years. The first question should be: what do we want our students to know and be able to do by the time they leave our school? The second question: how can we design and organise a curriculum that will cause this to happen? One of the answers lies in the subtle, purposeful and cumulative repetition of the underlying ideas, means of enquiry and processes that make our subjects tick. First of all, however, we need to work out what these are – no mean feat in itself!
Cumulative testing. A second answer lies in the implementation of well-organised and thoughtful assessment systems. Sadly, assessment is all too often the enemy of spaced practice. Our assessment systems should be completely tuned into the knowledge we want our students to retain for the future because, whether we like it or not, our students value what we assess. Assessment should emphasise portable, high-utility knowledge – i.e. the knowledge that students will take forward with them to inform their future learning. If we want students to remember something for the long term, it is simply not enough to assess this only once. It needs to be assessed on multiple occasions, which is why end-of-unit assessments should be designed not only around recently learned knowledge, but also concepts from previous units. This way, assessment not only gives us valuable information about student learning, but also provides an invaluable tool for spaced practice.
Retrospective homework. A simple strategy is to use homework as a way of giving students the chance to study previously learnt material. For instance, your weekly homework might involve quizzes or questions on previous units.
Pause lessons. Similarly, it is often a good idea to ‘pause’ the topic you are currently studying to go back to a topic covered before. This works best when it is carefully planned into a termly or yearly curriculum. Even though it might cause your students to grumble, sometimes it is a good idea to withhold assessment feedback for a week or two, rather than returning it immediately. This can activate the spaced practice effect, especially if your class are given a new task that allows them not only to hone and refine their knowledge, but allows them to re-practice this knowledge a few weeks on. Too often, students perform well in an end-of-term assessment, but do not get the opportunity to come back to this material in a meaningful way … and so it is forgotten.
Teach it. Lastly, it is crucial to remember that spaced practice does not sit comfortably with how students think that they learn. Spaced practice, therefore, is best taught in context. Merely telling students that they should space out their practice is unlikely to be effective. Instead they need to be shown what spaced practice looks like in mathematics, in English or in PE. In each subject, it is likely that a different emphasis is taken. Perhaps the most obvious first step is to explain explicitly why and how you are spacing out their practice in your lesson, curriculum and assessment structures. You should then provide structured opportunities for independent spaced practice, perhaps through homework or pre-prepared revision plans. Once spaced practice becomes a habit, then you are likely to be onto a winner.
Getting spaced practice wrong
Master it first. It is most useful to think of spaced practice as a revision tool. New topics often require a significant amount of ‘blocked teaching’ – in other words, a series of lessons on the same topic that build gradually so that students develop their knowledge slowly and meaningfully until they are eventually able to start making connections for themselves. It can be unwise to mix up topics during initial teaching as this can lead to confusion and superficial understanding.
Spacing is not interleaving. Interleaving is about studying more than one topic side-by-side in the same study session. Spacing, however, is about leaving increasingly longer gaps between study sessions. It is important to understand the difference between the two because there is, as yet, little evidence that ‘interleaving the curriculum’ – i.e. mixing up topics for initial teaching – provides an effective approach to curriculum design.
There are more important aspects to a successful curriculum. When applying any education research to the classroom, we must avoid putting the evidence cart before the curriculum horse. Spaced practice does not provide a solution to questions of curriculum content or effective pedagogy. A wonderfully spaced out curriculum is useless if it is also below par and taught ineffectively. However, once a strong curriculum and good teaching are successfully in place, spaced practice can help your students learn in a more effective and efficient manner.
And finally. Spacing is not just for exams. If learning is for life, then spaced practice is also a valuable life skill worth teaching in its own right.
Many thanks for reading.