It’s not unusual for students to forget what they have learnt – whether it be from a week ago, a term ago, or a year ago – but why do they forget? Learning is all about transferring information from our working memories to our long-term memories; the better we can do that, the less likely we are to forget things. We’ll often see students cramming in information, or rote learning formulae – this can help students keep up in class, but doesn’t support mastery learning, or connect understanding to long-term memory – so they simply won’t recall that information later. Even students who are engaged and enjoy their learning can have difficulty transferring all their knowledge to memory if it isn’t presented correctly, so it can seem that just as quickly as students learn a topic, they forget it. 

The three types of forgetting affecting students 

The three main processes believed to cause forgetting include decay, interference, and the absence of appropriate retrieval cues (Anderson, 2000; Bransford, 1979). Decay is commonly associated with short-term memory; the longer a student goes without revising information, the harder it will be to recall information.

Interference refers to the interactions between two sets of memories that can lead to confusing or combining knowledge in the long-term memory, disrupting the ability to recall the information. This can happen when two different but similar concepts are taught and students can’t differentiate between them. 

The final form of forgetting, common in students, is the absence of appropriate retrieval. This makes it challenging for students to recall information as they don’t have the necessary aids and cues to prompt them.

To help counteract forgetting Ausubel (2000) advised that a learner should establish a “stable trace” in memory. To be stable, the learner must be able to distinguish one concept from similar concepts to avoid interference. The learner must also connect the material to other relevant knowledge already possessed and thereby make the material meaningful and not simply rote memorisation. The more connections the learner can make, the more anchored the trace will be in memory, thereby increasing the number of useful retrieval cues that will be available to the learner (Bacon, Stewart, 2006)

The strategy connecting learning to long-term memory

The most popular and well-researched strategy widely used in education to promote mastery-based learning is spaced practice. A learning technique that involves reviewing learned information at increasing intervals. This approach to learning is highly effective as it commits the information to long-term memory.

The key to spaced repetition is timing. We don’t want to wait too long to review or we might completely forget the information. And too soon might mean the memory is not strengthened. We need to hit the sweet spot of reviewing learned information just before it’s forgotten. This idea is underpinned by one of Herman Ebbinghaus’ most important findings – Ebbinghaus’ Forgetting Curve. When we space out reviewing information at regular enough intervals, we don’t have a chance to completely forget it. In fact, when we review at the point of almost forgetting we make our memory stronger, as our brain reinforces the memory and adds new details. This is why revision strategies like practice tests and teaching what we have learnt to others are so effective. 

Spaced repetition has been consistently proven to be a highly effective learning strategy in research spanning over 100 years. Academic research has supported the practice of learning different types of information like definitions, trivia facts, and translation of foreign vocabulary as well as learning information across different domains, like Mathematics and Biology (Dunlosky, Rawson, Marsh, Nathan, & Willingham, 2013).

Research has identified a number of factors that contribute to its positive outcomes. The first factor suggests that reviewing information when we’re on the cusp of forgetting not only reinforces it but helps us to add new details to it. It’s at this point that we often realise what we’ve forgotten which can help us commit these details to long-term memory.

Another factor is when we regularly recall information, our brain will assign greater importance to it. That’s why it’s easier to remember the information related to things we do every day, like the directions to work, versus information we don’t recall very often, like the address of our dentist.

Research also shows that when we recall information using spaced practice our brains encode the information differently each time (Salisbury, David, 1990). This is because the harder information is to remember now, the easier it will be to remember in the future. It also explains why completing a practice test is more effective for learning than reviewing flashcards. When we have to work hard to recall something, or if something we’ve forgotten is highlighted, we’re more likely to commit it to memory, making for easier recall later. 

While most research on spaced repetition focuses on the improvement of memory, research also shows that it supports the transfer of learning (Kang, S.H.K 2016). This means that those who practice spaced repetition can use the information that they’ve learned to answer new questions or solve new problems. This suggests the learning is in fact, true, meaningful learning not just rote learning. 

How can you incorporate this in your teaching?

The four common schedules that can be employed as part of a spaced practice strategy include uniform, expanding, contracting, and mass. Each conducts its testing intervals at varying times, which is shown to have differing effects on memory. 

Image source: https://www.nature.com/articles/s41539-020-00074-4 

Research into the most effective form of spaced practice was completed by Eglington & Pavlik Jr. (2020). Their findings conclude that the expanding schedule is superior in improving learning and memory function. 

Landauer and Bjork also found that an expanding schedule of test trials without feedback resulted in better memory at a final test than both uniform and contracting schedules. There is empirical evidence that practice can slow forgetting, which implies that as practice accumulates retrieval becomes easier. This finding of slowed forgetting, in combination with study-phase retrieval theories, implies that gradually increasing difficulty (via spacing) may balance difficulty and lead to better memory via an expanding schedule (Eglington, Pavlik Jr. 2020).

Expanding schedule

Image source: https://www.nature.com/articles/s41539-020-00074-4 

Classroom resources that correctly apply spaced practice see impressive student outcomes compared to those resources and strategies that don’t have the capability. Maths Pathway students begin each day by completing a warm-up activity with six questions, automatically generated and personalised to their learning as a key way to incorporate spaced practice and reinforce prior learning. 

The warm-up feature was introduced into modules in August 2022. In June 2023, we integrated Eglington’s algorithm to select questions at expanding intervals, that are likely to provide students with a 90% success rate. The change in the accuracy of student responses was immediate, providing a more effective learning experience for students.

This comparison shows the improvement in accuracy in the warm-up activities before and after Eglington’s algorithm was implemented.

Along with warm-up activities students also participate in entry and exit activities, which occur before and after their main piece of personalised classroom work and relate directly to their task. This ensures students are ready to learn the next segment of content and then also grasp it well enough to move on. This reduces the risk of rote learning as students are continuously assessed to ensure mastery is taking place. 

Those using Maths Pathway love how easy it is to incorporate personalised learning along with spaced practice. Our educators are always confident their students are receiving the highest quality learning experience. 

Explore our program in a free trial to experience firsthand how we have utilised proven research and evidence-based practice to power our personalised learning model so that students can see outstanding long-term results. 

References 

Anderson, J. R. (2000). Leaming and memory (2nd ed.). New York: John Wiley.

Ausubel, D. P. (2000). The acquisition and retention of knowledge: A cognitive view. Norwell, MA: Kluwer Academic Publishers.

Bransford, J. D. (1979). Human cognition: Learning, understanding, and remembering. Belmont, CA: Wadsworth.

Donald R. Bacon and Kim A. Stewart. (2006). How Fast Do Students Forget What They Learn in Consumer Behavior? A Longitudinal Study. 

Dunlosky, J., Rawson, K. A., Marsh, E. J., Nathan, M. J., & Willingham, D. T. (2013). Improving students’ learning with effective learning techniques: Promising directions from cognitive and educational psychology. Psychological Science in the Public Interest,.

Luke G. Eglington & Philip I. Pavlik Jr. (2020). Optimizing practice scheduling requires quantitative tracking of individual item performance. npj Science of Learning.

Landauer, T. K. & Bjork, R. A. (1978). in Practical Aspects of Memory eds Gruneberg., M. M., Morris, P. E. & Sykes, R. N.

Salisbury, David F. (1990). Cognitive psychology and its implications for designing drill and practice programs for computers. Paper presented at the meeting of the American Educational Research Association, New Orleans, LA.

Kang, S.H.K (2016). Spaced Repetition Promotes Efficient and Effective Learning: Policy Implications for Instruction. Policy Insights from the Behavioral and Brain Sciences.