The Evidence on Teaching

Using Spacing to Enhance Diverse Forms of Learning: Review and Implications for Instruction

Carpenter, S. K., Cepeda, N. J., Rohrer, D., Kang, S. H. K., & Pashler, H. · 2012

grade Dreviewindependentreplicated
Sample
Narrative review
Population
Preschool to adults; facts, vocabulary, skills, some generalization.
Design
Review curating classroom-relevant spacing demonstrations and the optimal-gap parameter.
Key findings
Consolidates the practical rule: space repetitions at ~10-20% of the intended retention interval, and notes spacing helps not just facts but skills and some near-transfer generalization (math). Grade-D review evidence.
Genetic confound
N/A (review).
Replication notes
Standard source for the '10-20% of retention interval' heuristic; aligns with Cepeda 2008.
DOI / URL
10.1007/s10648-012-9205-z

Effects

OutcomeMetricValueMeasureTimingVsHorizonClass
Optimal spacing gap as proportion of retention interval% of test delay~10-20% of the desired retention intervalresearcher-designeddelayed; lab+classroomnoneuncleardomain-skill

Cited by