Ruth Corderoy relates what she learnt from Bjork and Bjork’s cognitive science research to learning and teaching economics.
We all know the feeling: you have taught a topic and a few weeks later students flatly deny they know anything about it. It is gone. Minds are blank. ‘Look, it’s in your notes!’, ‘Oh’, they say, ‘Yeah, sorry’. What has happened? Is it just that they have the memory of a goldfish or is there more to it? More importantly, is there a way of teaching that reduces the number of times this happens, that can make the learning a bit more secure?
A few years back Elizabeth and Robert Bjork published an article1 which cast some light on this perennial teaching problem and offers some practical solutions. They started by distinguishing between learning and performance: performance is what we can observe or measure during instruction (this is more than tests, it includes what we see happening in any lesson), learning is a long-term change in knowledge or understanding. The problem is that as research has shown, learning and performance are often not as closely related as teachers and students might hope. For example animals left to wander aimlessly around mazes with no incentives or training were shown to have learned quite a bit about that maze in subsequent runs. Other experiments have shown that substantial improvements in short-term performance can occur without any significant longer-term learning having taken place2, a phenomenon that every teacher knows as cramming for the test and forgetting the lot 10 minutes later.
Bjork and Bjork distinguish between storage strength (how firmly is it entrenched) and retrieval strength (ease of accessibility/activation) of information and skills stored in memory. They argue that current performance is a function of current retrieval strength but that storage strength acts to reduce loss (i.e. forgetting) and increase gain (re-learning) of retrieval. Economics teachers have quite a lot of economics specific knowledge permanently stored. For example, I don’t need MC=MR tattooed on my forearm to recall a firm’s profit maximising output level. I can describe the aggregate demand function with as little difficulty as I could tell you my name. The trouble is that this makes us underestimate the process by which this information became so ingrained. In truth, it sits in our consciousness waiting to be used following a whole series of learning events, some formal, some informal. In forgetting this as teachers, we don’t work on storage strength or we think it’s the same as retrieval strength, rather than something that improves retrieval. Bjork and Bjork argued that it is important to consider learning strategies that improve storage strength, because this will improve retrieval and thus performance.
The approach they came up with was to ‘create desirable difficulties’, i.e. the sort of difficulties that lead to long-term storage of information when the student tackles them. Bjork and Bjork identified a number of desirable difficulties:
a. Varying the conditions of learning
b. Interleaving instruction on different topics rather than grouping teaching by topic
c. Spacing rather than massing teaching on a given topic
d. Using tests as teaching (not necessarily assessment) events.
So how might these look when teaching economics?
Varying the conditions of learning
When we learn in the same place at the same time, learning tends to be context specific – walk into the economics room at 9am on a Monday and you trigger economics memories – the problem is that such learning isn’t very secure in a different time and place. School timetables make this tricky to address but moving rooms unexpectedly or encouraging students to vary where they do their own study can help, as can suddenly firing economics questions at them in school corridors, form time or lunch. Do this in the right way and the Sixth Form tend to like it as confirmatory evidence that you are unhinged, but not in a bad way, and it is likely that certain key bits of information or even small analytical paths (draw me a diagram showing the effects of advertising on the chocolate market, now!) become entrenched. Homework of course becomes doubly important but what about varying this too by introducing a synchronous online forum?
Spacing rather than massing teaching and interleaving instruction
These two ideas really go together because they complement each other.
The benefit of spacing is one of the most robust findings across the entire history of experimental research on learning and memory. It really isn’t disputed so it’s odd that we don’t do it. Shea and Morgan’s3 classic experiment showed that blocked practice (e.g. in economics a series of sessions on one concept) led to participants improving performance more rapidly than those given interleaved or random instruction. BUT crucially when participants returned after a period of time to be re-tested it was those who had been instructed with an interleaved programme who showed the best performance. Thus instruction and revision programmes that teach one topic, test it, then the next topic and test it, are not optimal.
The key finding is that blocked practice seems to improve performance because it improves short-term tests but interleaved practice leads to better long-term storage and retrieval. Roher and Taylor4 found that for learning formulae the size of the long-term advantage of interleaving over blocking was huge: 63% over 20% of new problems solved correctly a week later. Yet students tend to think that their performance is better if they are taught in blocks, probably because it feels easier and they are fooled by a short-term feeling of competence.
Bjork and Bjork think that spacing and interleaving work so well because they force students to notice similarities and differences in different material and they have to re-load their memories e.g. if you are asked to solve problem A, then B then A again you have to re-load compared to just doing a sequence of problem As; the act of re-loading strengthens the long-term storage.
The good news is that economics lends itself to this, so supply and demand, followed by indirect taxes, followed by supply and demand re-cap, followed by social costs and benefits, followed by indirect tax re-cap followed by a mixed test or case study of all concepts might be one approach.
Using tests as teaching events
By this I mean informal tests as teaching tools NOT high-stakes assessment tests (these have their place but are not particularly helpful for enhancing long-term storage). Low stakes unannounced informal tests make students have to try to retrieve and use information but without exam/assessment pressure. Research shows that tests force students to try to retrieve information from long-term memory and this effort makes storage more permanent and is far more effective than simply re-reading notes or even re-reading and highlighting key sentences. An example would be giving the whiteboard marker to a student with no warning and asking them to draw a diagram, or suddenly giving out rough paper and asking five questions. Better still get students to test each other by setting 5 questions as the setter will work doubly hard to come up with questions and in the process retrieve and think about a great deal of information. The technique can be done in lots of ways but the key is the sudden, unexpected retrieval and use of previously taught information.
It is worth repeating that this is NOT the same as frequent prior notice tests for assessment purposes, these tend to lead to short-term cramming and the illusion that short-term performance in such tests is an indicator of long-term secure learning. By all means do them if the system requires it (and it generally does!) but informal teaching-purpose tests where the results are not even recorded are much more effective at embedding learning than these assessment tests.
These informal tests are much more effective revision strategies than re-reading and a much more reliable indicator to a student of what they really know rather than think they know so it helps with metacognition too.
These methods can be combined so asking them suddenly to show the effect of an indirect tax but doing it in a lesson that is notionally about pollution and social and private costs has a double pay-off by retrieving and practising diagrams but also the juxtaposition helps them to realise for themselves that the two topics are very strongly related. Economics topics are all linked of course and the constant retrieval of key concepts at unexpected times and in different contexts will help to make that clear and also embed such key ideas.
The ideal result of our teaching is that our students don’t forget their economics the day after an exam but that the key concepts are lodged with them permanently, as they are for us, their teachers.
Ruth Corderoy is a Senior Lecturer at the University of Buckingham.
1. Bjork, E. L., & Bjork, R. A. (2011). Making things hard on yourself, but in a good way: Creating desirable difficulties to enhance learning. In M. A. Gernsbacher, R. W. Pew, L. M. Hough, & J. R. Pomerantz (Eds.), Psychology and the realworld: Essays illustrating fundamental contributions to society (pp. 56–64). New York, NY: Worth Publishers.
2. e.g. Bjork, R. A., & Bjork, E. L. (1992). A new theory of disuse and an old theory of stimulus fluctuation. In A. Healy, S. Kosslyn, & R. Shiffrin (Eds.), From learning processes to cognitive processes: Essays in honor of William K. Estes (Vol. 2, pp. 35–67). Hillsdale, NJ: Erlbaum.
3. Shea, J. B., & Morgan, R. L. (1979). Contextual interference effects on the acquisition, retention, and transfer of a motor skill. Journal of Experimental Psychology: Human Learning and Memory, 5, 179–187.
4. Rohrer, D., & Taylor, K. (2007). The shuffling of mathematics problems improves learning. Instructional Science, 35, 481–498.
6. Soderstrom, N.C. and Bjork, R.A. (2015) Learning versus performance: an integrative review. Perspectives on Psychological Science Vol 10(2) 176-199