The theory of Montessori education has been interpreted by some researchers to be vaguely formulated. However, as shown in previous research, Maria Montessori’s didactic approach to teaching and learning mathematics is fully consistent with variation theory and the theory of embodiment. Montessori used the theoretical concept of isolation of quality, which means that the learning objects have to be kept identical except for one variable, which has to differ to be perceptible. This concept is in alignment with variation theory, which emphasizes variation as a necessary condition for learners to discern aspects of an object of learning. The other theory applied in this article is the theory of embodiment: important cognitive functions are fundamentally grounded in action that is concordant with Montessori’s view that mind and movement are parts of the same entity.

This article reports on a qualitative single-case study with a formative intention in which we investigated the significance of being acquainted with variation theory and the theory of embodiment when working with Montessori material. The study analyzes a teacher’s mathematics presentations with the Montessori material and the children’s work with this material, using Epistemological Move Analysis, which focuses on how the teacher directs children’s learning. The analysis was shared with the teacher to support her awareness of the ways teaching can be developed from a variation and embodiment theoretical perspective. Results show that the teacher’s awareness of why a specific learning object be treated in accordance with variation theory and embodiment seems to promote a more constructive and effective way to direct children’s learning.