Highland’s Montessori curriculum spans six years, three years of preschool and the first three of elementary school. This chapter describes the Montessori model and reviews relevant research on it. Classroom observations and teacher interviews flesh out descriptions of Highlands Children’s House and Junior Level. The chapter highlights how Highland has augmented the Montessori model. It briefly sketches the interaction of the three tripods of the Montessori model: the child, the environment, and the adult. The term “Montessori” refers to the philosophy and pedagogical practices of Maria Montessori, Italy’s first woman physician, who established schools for the children of Rome’s slums at the turn of the century.