Dr. Montessori, in her initial work in 1907 in San Lorenzo, observed that the younger children were intensely attracted to sensory development apparatus. The children used these materials spontaneously, independently, repeatedly and with deep concentration. They emerged from this spontaneous activity renewed and with a profound sense of inner satisfaction.
"Montessori method is based on the spontaneous activity of the child which is aroused precisely by the interest the child takes in the material."
From this initial discovery, over many years of observation and trial and error, Dr. Montessori and her son Mario, went on to design an entire range of Montessori materials.
In order for the materials to be of optimum benefit they must be presented to the child at the appropriate stage in his or her development by a trained Montessori teacher. The materials then allow the child to engage in self-directed, purposeful activity. The materials are beautiful and enticing and are displayed in an orderly and accessible way.
"All the apparatus must be meticulously in order, beautiful and shiny, in perfect condition. Nothing must be missing, so that to the child it always seems new, complete and ready for use."
Today, the Association Montessori Internationale Pedagogical Committee continues to oversee the development and manufacture of the Montessori materials.