An Intervention Study: Removing Supplemented Materials from Montessori Classrooms Associated with Better Child Outcomes




Montessori, early childhood education


Montessori classrooms vary a good deal in implementation, and one way in which implementation differs is the provision of materials.  Specifically, some classrooms use only Montessori materials, whereas others supplement the Montessori materials with commercially available materials like puzzles and games.  A prior study suggested this might be a reason for observed differences across studies and classrooms (Author, 2012) but an intervention study is the best test.  The present study presents such an intervention with 52 children in 3 Montessori classrooms with Supplementary materials. All children were given 6 pretests, and non-Montessori materials were removed from 2 of the classrooms.  Four months later, children were retested to see how much they changed across that period.  Children in the classrooms from which the non-Montessori materials were removed advanced significantly more in early reading and executive function, and to some degree advanced more in early math.  There were no differences across the classroom types in amount of change on the tests of vocabulary, social knowledge, or social skills.

Author Biography

Angeline S Lillard, University of Virginia

Professor of Psychology


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How to Cite

Lillard, A. S., & Heise, M. J. (2016). An Intervention Study: Removing Supplemented Materials from Montessori Classrooms Associated with Better Child Outcomes. Journal of Montessori Research, 2(1), 16–26.