Variation can be a desirable difficulty. Image by Pixabay.
Recently I gave a lecture on desirable difficulties focusing especially on variation and spacing, linking to this article by Robert Bjork. I also covered the limited benefits of overlearning. In the follow-up tutorial, students (2nd year undergraduates) were asked to come up with questions. Here are some of their questions, together with my responses:
1) In what circumstances is variation most valuable?
Variation is valuable in circumstances when the eventual use of the knowledge or skill is unpredictable. If you know exactly when and how you are going to use what you have learned, then varying the practice becomes unnecessary. For example, if you drive a Mini and plan to do so for the rest of your life, then there is no need to practice with other types of car. If you are only every going to hit a golf ball in the driving range then you don’t need to practice hitting the ball off a slope, off sand, out of long grass etc. However if you would like a more flexible skill that would allow you to adapt to unexpected situations, then you should vary your practice.
2) It can be difficult to use variation all the time in the classroom, so how can you judge when it will be most valuable to use it? What about if you’re stuck in the classroom with limited resources?
Often, we teach learners in school with a view to preparing them for a future which is inherently unpredictable, and so varied practice is probably a good idea for all subjects and topics. But if you have to choose, then focus on the things that are hardest to transfer (perhaps because they are complex or conceptual) and the ones which are most useful. Mathematics is a good example – it is very useful and important to be able to transfer it to new situations, but also quite complex for learners. As to limited resources, variation doesn’t necessarily require changing all that much in terms of resources or materials. It could involve adding a real-world context to a maths or science problem, or moving location to practice (e.g. outdoor learning). In my teaching subject (psychology) it might involve giving learners a real-world scenario in which to apply their learning of a concept such as conformity or altruism, and that could be done verbally or using a whiteboard or slide. There are many ways of varying the learning – just try to avoid repetitions of exactly the same format of problem or task. This is too easy for learners, and doesn’t help them to later use their knowledge flexibly.
3) Is variation more effective for learning knowledge or skills?
In both cases, it makes learning easier to transfer to novel situations. Many (perhaps all) tasks require both knowledge and skill; reading, for example, draws on your knowledge of what you are reading about, as well as skills such as decoding. It’s difficult to separate or compare these, but it should be helpful for both.
4) How do you best take advantage of the spacing effect in the classroom?
Perhaps the best ways are the simplest. One of the nice things about the spacing effect is that you don’t need to change very much – you can just modify the timing of a task. So the practice that you have already planned and resourced can be scheduled for a week later. Spacing homework is worth considering because a delay will lead to more effective consolidation, but bear in mind that not every pupil completes their homework, and some may find it too difficult after a delay. A very simple way to implement spacing is to have a brief test or quiz at the start of a lesson, drawing on material from a few weeks earlier. Another option is to set broad project-style tasks that require knowledge of older material, not just the most recently-studied topic.
5) What about individual learner needs – i.e. when it becomes overlearning for some children, but some still need more time to master a skill. Are there any ideas of how this can be managed in the classroom?
Yes, it is quite individual. Overlearning means practicing beyond the point of mastery, and different learners master a task at different rates. So there will come a point that some students would be best to stop/switch and others should keep going. This is much the same as managing any differentiation in the classroom. Some learners may benefit more from an extension task, perhaps one that brings in older knowledge or changes the context, while others need more time to master the basics. One thing to bear in mind, though, is that learners don’t always have a clear insight into whether they have mastered something, so don’t always rely on their making this choice themselves.
6) How do you know if something is a desirable difficulty?
A good question, and we should remember that not all difficulties are desirable! Let’s consider two phases – a training phase when we first learn something, and a using phase where we apply the knowledge or skills in our real lives. One key idea from the literature (e.g. the work of Bjork, 2018; McDaniel & Einstein, 2005) is that a difficulty is desirable if the processing that it prompts during the training phase is similar to something that a person will need to do in the using phase. So for example, spacing is helpful because in real life we often need to recall things after a delay. Variation is helpful because in real life the places and situations where we need to apply our learning are varied. A difficulty such as standing on your head to study would not be helpful unless that is something that you often do in your everyday life when applying your knowledge.
7) What is the role of professional judgment?
I think a key point about applying research to practice in general is that it doesn’t take away or undermine the importance of judgement. The professional educator is still in the best position to judge what is needed – but that judgement should be based on facts, not on myths and misconceptions. The case of the spacing effect is a good example. Teachers often misjudge this, mistakenly thinking that massing would be a superior strategy. But even after engaging with the literature and learning that it will be a good idea to delay practice, how long should it be delayed? The answer to that question will depend on both the learners and the material. You as a professional will need to make a judgement of how rapidly the learners are likely to forget, and aim to schedule practice when they are on the point of forgetting but haven’t entirely forgotten – so that retrieving and practicing the material is effortful but possible.
8) What about the interplay between desirable difficulties and learner confidence?
Linking to the question above, this is again a key area where professional judgement can play a role. When I first started applying spacing and interleaving in the classroom, I found that I had some Higher pupils who were doing well but who weren’t enjoying the experience very much (perhaps because they had spent 12 years of schooling doing practice that was very easy for them). There are various ways to manage this. Ideally you can persuade a class that difficult practice is worthwhile and fun, and that practice that is too easy is boring. Some pupils may feel anxious if they are getting answers wrong, and it will be important to emphasise that this is all right, and doesn’t mean that they are failing. Hopefully, if well managed, desirable difficulties will reduce anxiety over time, and boost confidence because learners realise that they are improving and developing sound knowledge (Agarwal et al, 2014, found evidence that application of desirable difficulties such as retrieval practice reduces anxiety in school pupils, for example).
9) Does it become an undesirable difficulty if a learner’s confidence drops too low for them to be motivated to keep going with the learning?
Yes, it would. There has to be a trade-off between doing something that is effective and any emotional impact that it has. I think this is very true of study/revision skills. We can make some generalisations about what is more effective and what is less effective when revising, but if the learner hates doing the better strategy then it might put them off studying altogether. That wouldn’t be helpful, and in some cases it might be better for them to just study the way they enjoy. For that reason, when it comes to changing learners’ study habits, I think that there has to be some ownership on the part the learner – they need to understand and want it – and it is often best to make changes one step at a time.
10) What is the most effective way to use desirable difficulties, and the best time to introduce them?
As they are superior to the alternatives (spacing is more effective than massing, etc), ideally it would be best to start using them straight away, and in all aspects of teaching and learning! Most of the changes involve pretty minimal effort on the part of the teacher/instructor. Having said that, any change can take planning and focus, and it may be valuable to go through a process of application followed by professional reflection, developing one topic or area of the curriculum at a time. You could also try to gather some data as you go along, perhaps as part of a practitioner enquiry research project.
Many thanks to our Strathclyde 2nd year classes for their fab questions!
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Related post – Spacing and interleaving in the STEM classroom
Further reading – You can read more about overlearning in this short article. You can also explore many of the ways that spacing can be applied to teaching and learning via my co-authored book, Psychology in the Classroom
Agarwal, P. K., D’Antonio, L., Roediger III, H. L., McDermott, K. B., & McDaniel, M. A. (2014). Classroom-based programs of retrieval practice reduce middle school and high school students’ test anxiety. Journal of Applied Research in Memory and Cognition, 3(3), 131-139.
Bjork, R. A. (2018). Being suspicious of the sense of ease and undeterred by the sense of difficulty: Looking back at Schmidt and Bjork (1992). Perspectives on Psychological Science, 13(2), 146-148.
McDaniel, M. A., & Einstein, G. O. (2005). Material appropriate difficulty: A framework for determining when difficulty is desirable for improving learning. In A. F. Healy (Ed.), Decade of behavior. Experimental cognitive psychology and its applications (pp. 73-85). Washington, DC: American Psychological Association.