One of the 4 techniques, associated with learning gain, used by the timely practice system - with the aid of the timely practice app.
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"Since the spacing effect was first discovered by Ebbinghaus in 1885, research has consistently shown that learning performance improves if multiple study sessions are separated in time (or “spaced”) rather than massed together. The effect occurs for adults, pre-schoolers and infants, and primary and secondary school children. A brain imaging study suggests the spacing effect in verbal learning is due to enhanced maintenance rehearsal (i.e. additional thinking about the material) in spaced, relative to massed presentations."(page 30) file
https:///Users/Leg/Documents/EEF_Lit_Review_NeuroscienceAndEducation.pdfv1.educationendowmentfoundation.org.uk/uploads/pdf/NSED_LitReview_Final.pdf (page 29 to 30)
More readable references
Review of "Make it Stick" The Science of Successful Learning
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