Planes of Development-Ages 2.9 to 12
Dr. Maria Montessori identified what she called planes of development. Through careful study and observation, she discovered that human beings progress through a series of planes or stages, each of which exhibit a particular pattern of growth. Dr. Montessori compared this progress to a “series of rebirths” (Absorbent Mind, 17). She illustrated this concept by depicting a line of four triangles representing the specific ages.
Each plane lasts six years and represents sensitive periods of development. These are times of special learning opportunities. The stages from 0 to 6 and 6 to 12 years of age are the most dynamic periods of intellectual, social, personal, and physical growth. The red lines represent the strengthening of the unique sensitivities of a given plane. The bottom row of numbers show the ages where the sensitivities are at their strongest.