Maria Montessori's research identified four unique stages of development from birth to early adulthood, which she called planes of development. She observed that each plane is characterised by specific sensitive periods where children display particular needs, characteristics, and behaviours. During these sensitive periods, children experience intense developmental transformations, after which comes a period of consolidation. In this phase, children display a newfound confidence in the skills they have acquired.
From birth to the age of six, children’s development is categorised into two stages: from birth to three years old and from three to six years old. During this time, children typically divide their time between home and school.