In Montessori pedagogy, the "First Plane" refers to the developmental stage from birth to around six years of age. This period is characterised by rapid physical, cognitive, and emotional growth, during which the child is seen as an "absorbent mind." Maria Montessori observed that children at this stage have an extraordinary ability to absorb information from their environment effortlessly and unconsciously. They learn through exploration and sensory experiences, constructing their understanding of the world through interaction and imitation. The First Plane is divided into two sub-phases: from birth to three years, when the child learns primarily through unconscious absorption, and from three to six years, when learning becomes more conscious and deliberate. During this time, Montessori education focuses on nurturing independence, practical life skills, sensory development, and language acquisition, providing a prepared environment where the child can follow their natural developmental needs. The First Plane is foundational, as it sets the stage for all future learning and development.

“The greatness of the human personality begins at the hour of birth…the child has a mind able to absorb knowledge. He has the power to teach himself.” (Montessori, Maria, The Absorbent Mind, pp 2-3) “The first period… was for the absorption of the environment.” (Montessori, Maria, To Educate the Human Potential, p. 1) “Between the ages of two and four, there is a sensory, and, at the same time, intellectual stage…” (Montessori, Maria, The Child Society and the World, p. 31) “One characteristic of children under six years of age is that it is almost impossible to teach them…these children must take knowledge by themselves from the environment.” (Montessori, Maria, The Child, Society, and the World, p. 42) “…we can only deduce that there is a special predisposition at this early age to mathematics.” (Montessori, Maria, Education for a New World, p. 7) “Not only do they seem indefatigable, but by being intellectually active they acquire strength and health.” (Montessori, Maria, The Child, Society, and the World, p. 8)