Why nearly forgetting is actually a good thing

What is it? Spacing was first introduced by the German psychologist Hermann Ebbinghaus, in 1885.

He said people will forget things they only study once, and that we need to encounter the same information seven times if we want to embed it in our long-term memory. 

In current classroom practice, this means leaving increasing intervals in time between teaching content and re-studying it. This means students nearly forget before being exposed to the same knowledge again.

What does this look like in the classroom? Students may be asked to re-study definitions of key terms, practise the introduction to an essay or factorise an equation. 

They would initially do this in the lesson after first encountering it, then perhaps again a week later, then a month later, and so on.

What might this look like on the field? The chart below is an example for lineout calls. 

^{The coloured lines in the above example not only indicate increased gaps between re-studying the lineout call, but also the increase in difficulty for players in remembering it. This is a good thing – the more cognitive effort required to recall from long-term memory, the more likely the information (in this case, the lineout call) will be remembered next time.}

This is working on the assumption that players may train only once a week. If you train twice or even three times a week, you may want to increase the number of training sessions between practising lineouts.

Benefits of this approach: Each time players are required to re-study this knowledge after increasing time intervals, it is likely to become easier to recall and, subsequently, easier to remember next time.

Pitfalls of this approach: Spacing focuses on recalling the same knowledge.

However, to develop meaningful understanding, players must go further than just revisiting the same knowledge or skill, or move in isolation. They must make connections between new knowledge and prior knowledge. 

This approach alone does not allow players to make these connections. Learning becomes rote, and is disconnected and isolated. 

This results in the information being forgotten in the long term, because it is not meaningfully connected to the other memories. 

Interleaving

What is it? The concept of switching between topics, instead of teaching them in blocks (see graphic, below).

Interleaving is not the same as spacing. It does contain elements of it – for example, a large gap in time between studying a topic before revisiting it. Successful interleaving, though, must involve topics that are similarly different. They must be related in some way, so students or players can discern the similarities and differences between them.

What does this look like in the classroom? In an English Literature lesson, it might involve teaching different poems back-to-back, so students can make connections between themes, structures, styles and devices; rather than a topic on essay writing, followed by reading a novel, and a lesson on a poem.

What might this look like on the field? See the graphic below. 

It shows the benefits of interleaving, in terms of discerning similarities and differences between similar concepts, allowing players to develop meaningful and long-lasting understanding.

Benefits of this approach: Placing topics or concepts that share some similarities next to each other allows students or players to compare and contrast examples.

This strengthens their memory associations, as they make connections between current and prior knowledge, and leads to deeper understanding and a greater chance of meaningful long-term learning.

Pitfalls of this approach:  Assumption. Coaches and teachers must give players/students the opportunity to make connections, and not assume they will make them on their own (hint: they will not!). 

Summary

Spacing and interleaving serve different purposes in terms of their outcomes. 

Spacing helps us recall state of fact from our long-term memory, making the fact more accessible each time we do.

Interleaving allows us to sequence and coach concepts that are similarly different. This allows for meaningful connections and deeper, long-term understanding and learning. It also has the bonus of spacing.

Questions to consider

• For an upcoming sequence of training sessions, when could players benefit from spaced practice?
• Think about the purpose of your upcoming session. When could you use the interleaving tool above to map out the similarities and differences between session topics?
• How is your training plan mapped? Could you adapt it to reap interleaving’s benefits?
• How will you make the similarities and differences obvious to players? Where could you build in opportunities for them to think deeply about the links?
• Purpose: Is interleaving always appropriate in your rugby curriculum/training plan?