The Retention Toolkit is a series of posts describing research based tools which help improve long-term knowledge retention.
In my first post of this series, I presented research on test-enhanced learning: using testing not as an evaluation technique, but as a learning technique to improve retention. Testing is a far more efficient use of time than study techniques such as rereading, reviewing lecture notes, or making outlines.
But how is test-enhanced learning best implemented? Research in human memory shows that timing is everything. It’s called the spacing effect.
Information that is spaced over time is better remembered than the same amount of information massed together.(1)
Take a look at this graphic of memorization over time. New material is presented on day 0. It is then studied at gradually increasing intervals. The intervals double approximately after each successful retrieval (test) from memory. Over time, the rate of forgetting (slope of the blue line) approaches zero, even though the material is being retrieved less and less often.
Further, retention is boosted the most when a memory is just about to be forgotten. (1,2) Simply reviewing on a daily or weekly basis is not an efficient use of time or energy. Long-term, a review period of once every two months seems to maximize retention for life. (2) But how do we get from a new piece of information to a retrieval practice once every two months, especially when we consider that we want our students learning a LOT of new pieces of information every day and retaining them?
First, use an effective study method: Teach students to self-test, rather than review material passively. Second, revisit material on an expanding review schedule, as described in the next section.
Application in the Homeschool
There are three possibilities:
- Informal test-enhanced learning
- Scheduled test-enhanced learning with a paper system
- Scheduled test-enhanced learning with a computer system
You may find a combination of all three, based on subject matter and grade level.
When you are working closely with a student during each lesson, you may find you have an instinctive feel for what topics need to be revisited. You can perform a parent-guided retrieval practice in written or oral form, such as in these examples:
- Prior to a math lesson, write out ten warm-up problems which include topics from the last six months. Concentrate on newer concepts or concepts your student is struggling with. In our home, this work is done while I glance at the teacher’s book for the day’s lesson to get my footing.
- Before starting a new chapter in a read-aloud, ask your students to help you recall what has already happened, and what they think might happen next.
- Take a hint from public schools, and give your child “homework.” Go over a lesson and do several example problems. Then, rather than having the student immediately attack their independent work (spelling lists, math drills, verb conjugations…), set it aside and move to a new subject. When your student is ready to complete their homework, it will serve as a first review, rather than as a long lesson.
Scheduled Testing with a Paper System
If your curriculum includes a lot of memorization, you may find it is too hard to keep track of which Latin root, which insect order, and which historic event each of your children is currently struggling to remember. You can create a file card system that is based on spaced repetition, and use it daily for retrieval practice. Simply Charlotte Mason has created a scripture memory system that is easily adapted for any fact memorization. Watch this video for details.
Scheduled Testing with a Computer System
Some of the best work in spaced repetition systems was done by pioneering software designers, who tried various algorithms of testing frequency until they had found the most effective. We use Anki, but there are many other available- see the list on Wikipedia. All of these programs are intelligent flash card programs. They are incredibly powerful tools, and best suited to subject areas with large amounts of memorization: foreign language, specialized vocabulary (i.e. medical, legal), etc. However, they can also replace a paper system for family memory work, especially when mom or dad uses the computer to prompt retrieval practice across a broad subject range as part of a morning circle time or other general review time. I will go into much more detail about the power of Anki when I review Fluent Forever.
What if a student misses the ideal window, and is unable to remember the desired information at the next study session?
Step 1: Remaster the material immediately. Self-test at 1-2 minute intervals during a study session until you have reliably relearned the material. It does not take nearly as long to relearn a forgotten piece of information as it does to learn a new piece, so take heart!
- Step 2:
- If you need to have the material solidly memorized in the near term (1-2 weeks or months, for example when studying for an exam), then move that piece of information back to the very first slot in your card review system. If you are using a computer based program, this will be done automatically!
- If you are looking for retention over a much longer time period (years, or a lifetime), leave the card where it is, with a spaced retrieval planned for no more than two months away. (2) Over the long term (five year study) this works.
Charlotte Mason may not have heard of the spacing effect, but she certainly knew how to use it. She suggested reading books at a snail’s pace: often one chapter per week, with perhaps 10-20 books being read in this incremental fashion during the same time period. Presenting information in this way is a great example of the spacing effect. A book read over four months is much more likely to be remembered than one read over four hours.
Mason was also a proponent of short lessons, regularly given. We know from research that there is cognitive science backing her up. Two thirty minute lessons are far more memorable than a single one hour lesson.
Next in the Retention Toolkit, I will be looking at research supporting a move form a skill-centered approach to a content-centered approach to education.
(1) Sisti, H. M., Glass, A. L., & Shors, T. J. (2007). Neurogenesis and the spacing effect: learning over time enhances memory and the survival of new neurons. Learning & memory, 14(5), 368-375.
(2) Bahrick, H. P., Bahrick, L. E., Bahrick, A. S., & Bahrick, P. E. (1993). Maintenance of foreign language vocabulary and the spacing effect. Psychological Science, 4(5), 316-321.
In addition to these sources, this post contains a summary of the spacing effect information contained in this article:
Roediger, Henry L. et al. The critical role of retrieval practice in long-term retention. Trends in Cognitive Sciences, Volume 15, Issue 1, 20-27. 2010