Distributing Learning Over Time: The Spacing Effect in Children’s Acquisition and Generalization of Science Concepts


  • We thank Lauren Burakowski, Noel Enyedy, and Mariel Kyger for their feedback on this paper. We also thank the undergraduate research assistants of the Language and Cognitive Development Lab for their help with this project. We appreciate the help of the staff, teachers, and students of the UCLA Lab School. This study was supported by a CONNECT fellowship/grant and NICHD Grant R03 HD064909-01.

concerning this article should be addressed to Haley A. Vlach, Department of Psychology, 1285 Franz Hall, UCLA, Los Angeles, CA 90095. Electronic mail may be sent to haleyvlach@ucla.edu.


The spacing effect describes the robust finding that long-term learning is promoted when learning events are spaced out in time rather than presented in immediate succession. Studies of the spacing effect have focused on memory processes rather than for other types of learning, such as the acquisition and generalization of new concepts. In this study, early elementary school children (5- to 7-year-olds; = 36) were presented with science lessons on 1 of 3 schedules: massed, clumped, and spaced. The results revealed that spacing lessons out in time resulted in higher generalization performance for both simple and complex concepts. Spaced learning schedules promote several types of learning, strengthening the implications of the spacing effect for educational practices and curriculum.