Spreading learning over time may be an old idea but it's very effective. 

We can use what we know about learning and memory to design better learning experiences.  One of the strongest principles of learning is that learning takes time.  If we can divide our training into several sessions instead of a using a single longer session, our training will be more effective and our students will be better able to remember and use the new information.    

Here’s an example of how that might work; Carlos is a nurse manager who needs to help his team learn a new procedure.  When he’s needed to do training in the past, Carlos has blocked off a large chunk of time to demonstrate new procedures and let his nurses practice them.  This is not a bad strategy, having people learn about, then practice a new technique is often an effective way to help them learn.  

But Carlos can do something that will make his training sessions even more effective.  Instead of a single session where he shows his nurses how to do the new procedure and then gives them a chance to practice it, he can spread the same amount of instruction over two or three shorter daily sessions.  

Why is it important to divide the learning sessions?  Spreading learning out over time, sometimes called spaced learning or spaced practice, is one of the most effective ways to improve learning and memory.  

Interestingly, it works not just for humans, but it is a general property of learning for different species.  For instance, researchers, examining the effects of spacing on memory have taught honeybees to react to certain odors by extending their proboscises.  Bees have been taught to react to odor A, but not to Odor B, and they’ve been taught more complex reactions like reacting to odors a and B together, but not A or B by itself.  These memories are stronger if the learning sessions have been spaced out over time.1

This spacing effect is not a new idea; it was first described by Herman Ebbinghaus, a psychologist who did groundbreaking work on memory starting in 1879.  Ebbinghaus discovered many basic features of memory including the spacing effect.  Ebbinghaus used himself as a subject, memorizing many individual items and tracking his ability to remember them.  He discovered that he could improve his ability to remember items by spacing spacing his learning sessions over time, instead learning them in a single session.  

Carlos can use these principles to improve the training he’s giving to his nurses.  Spacing the learning sessions over time will improve the chances that his nurses will remember the new procedure and be able to use it effectively with patients.  Instead of using a single hour or two to learn the procedure, Carlos could break the up the learning into shorter 15 or 20 minute sessions over several days.  It might take a little more work on Carlos’ part to arrange this training but his benefit because they will have a much better chance of using the new procedure successfully.  

1. Menzel, R., Maz, G., Menzel, R., and U. Greggers (2001), Massed and spaced learning in honeybees: The role of CS, US, the interval, and the test interval.  Learning and Memory, 8:198-208.