This review examines the quantitative behavioural studies that have evaluated the effects of Montessori pedagogy on children's psychological development and school learning. The analyses of only three "Randomized Controlled Trials-RCT" studies published to date reveal varied and contradictory effects. Firstly, these findings are discussed in the light of several methodological limitations: the absence of active control groups, small sample sizes, diversity of measures, or lack of control over the implementation fidelity of both Montessori and conventional pedagogy. Secondly, these findings are discussed in the light of what Montessori pedagogy does not emphasise in its conception of development and the role of the teacher, namely the place given to language and pretend play.
