ResearchLong-term cohort studyEvidence: Small studyAges 3–6
Montessori Preschool Elevates and Equalizes Child Outcomes: A Longitudinal Study
Author or publisher Lillard et al., Frontiers in Psychology Published 2017 Reviewed by eduStack editors Last checked 13 Nov 2026
1What the study found
Following 141 children admitted to public preschools by lottery for 3 years, those in Montessori classrooms did better over time on academic achievement and social understanding, and the gap between lower- and higher-income children narrowed.
2Sources and check record
https://doi.org/10.3389/fpsyg.2017.01783 Lillard et al., Frontiers in Psychology. Montessori Preschool Elevates and Equalizes Child Outcomes: A Longitudinal Study. 2017. doi:10.3389/fpsyg.2017.01783 Last checked · 13 Nov 2026