By Megan Sumeracki
For over a century cognitive psychologists have been studying spaced practice and retrieval practice, resulting in a great deal of evidence that these two strategies work very well to improve student learning. However, no single experiment or paper is going to be able to answer, in full, the question “how does this strategy work in education?”. When we point to a single experiment, or even a set of experiments, it can be quite easy to point out the ways in which the experiment(s) may not be a perfect test of the phenomenon, or might not measure everything we want to measure. Each experiment or set of experiments has strengths and limitations, but by conducting the research in a lot of different ways, we gain more confidence in the recommendations and better understand the way these processes work. (Of course, we still have plenty of work to do as not every nuanced question has been answered.)
There are a few common criticisms of retrieval practice and spaced practice experiments that come up frequently. One is that we often use very simple materials. We explain why this is necessary when we write or talk about the lab-to-classroom model (see this post). However, even when we engage in applied laboratory and applied classroom research, the criticism often becomes that we are only looking at relatively short-term learning (e.g., a few days or weeks) and/or that we are measuring things like memorization, simple remembering, or fact learning. I would argue that learning and remembering facts is important, and the basis for being able to then apply that information in new settings (see this piece by Daniel Willingham). However, the research really does not stop at “memorization”! Many experiments have investigated what strategies help students make inferences, apply what they have learned to new problems or situations, and to generally transfer what they have learned (see this post and this post to read more about transfer). Again, while we have not answered all of the questions, I am confident in saying that spaced practice and retrieval practice do generally help students truly learn and apply what they have learned even after a longer delay.
In the spirit of addressing true student learning and their ability to take what they have learned with them into new situations, today’s blog covers a paper by Robin Hopkins and colleagues (1). They asked whether spaced retrieval practice throughout a precalculus class would help engineering students learn precalculus and perform better on the precalculus course’ cumulative final exam, and whether spaced retrieval practice during precalculus would better prepare them for the following semester’s calculus class.
Overall, what the results show is that yes, spaced retrieval practice during precalculus does lead to better performance in (1) precalculus and (2) on a cumulative final exam in the next semester’s calculus course many months later! This experiment is impressive. Read on to learn about the overall experimental methods and results.