Researchers Education researchers usually now talk of increasing interval retrieval practice rather than a whereas spaced repetition system, which is favoured by computer programmers.
An increasing interval retrieval practice or spaced repetition system (SRS) is a method to increase memory retention by multiple timely reviews.
What teachers generally call retrieval practice and researchers generally call spaced learning relies on the what is called the spacing or testing effect - if we practice something after some, but not too much forgetting has happened we will increase the duration of the retention.
Video on how the spaced repetition system works
increaseLTMduration.mp4
We are all forgetting all the time
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He called the graph below the forgetting curve, or since he was German, die Vergessenskurve1
It shows that as time goes on, memory fades.
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1 see a nice graph in https://de.wikipedia.org/wiki/Vergessenskurve Über das Gedächtnis. Untersuchungen zur experimentellen Psychologie. Duncker & Humblot, Leipzig 1885 and https://en.wikipedia.org/wiki/Forgetting_curve to read about it in English.
Video on how the spaced repetition system works
This is the same video found on the first page of Explaining and Training increaseLTMduration.mp4 - you might want to watch only the first 3 minutes.
Forgetting in low attaining classes.
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The timely practice app is designed so that maths teachers will to be able to get all their learners to review all their work in a timely manner.
Moreover the app is designed so that the teacher can “see” when their learners are ready to learn new, harder work.
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