Dr. Maria Montessori, one of Italy’s first female medical doctors, was assigned bin 1896 to an Orthophrenic school for children with developmental disabilities. As a trained medical doctor, not an educator, Dr. Montessori implemented the scientific method of hypothesis, observation, analysis, and conclusion in her service to the children at the Orthophrenic school. Drawing upon the research, tools, and discoveries of her peers and predecessors in special education (Froebel, Itard, and Seguin), she introduced scientifically designed materials to the students, and measured their effectiveness. By the end of her short tenure at the Orthophrenic school in Rome, Montessori’s students tested at or above the national average for academic achievement.
These early successes caused Dr. Montessori to wonder what affects these didactic materials might have when implemented and studied in “normal” schools. She accepted a position with a housing development in San Lorenzo, Italy to develop a program to occupy unsupervised, unruly children while their parents worked. Here again, in the first Montessori School, she discovered the success of the hands-on, auto-didactic materials to engage the children in meaningful work that served to assist them physically, academically, and socially.
As the Montessori Method spread throughout the world during the 20th century, Montessori ceaselessly continued to develop her unique method of education to address the unique needs of children of all ages – birth through maturity. Concomitantly, advances in neuroscientific research have confirmed that the nine principles of Montessori education, as she laid out in her book The Montessori Method, do best foster the developing human brain throughout its development. These nine principles are: Movement and cognition have a symbiotic relationship, learning and well-being improve when given manageable freedom of choice, attention to a singular task leads to deep concentration, people learn best when interested in a particular topic or task, intrinsic rewards have a higher motivational value than extrinsic rewards, collaborative learning arrangements benefit all parties, learning happens best within a meaningful context, the relationship between the adult teacher and the child is paramount to success in school, and students thrive in orderly environments.
With these principles as a foundation, authentic Montessori environments implement the specialized Montessori materials for children in four universal categories: Practical Life, Sensorial, Language, and Math. Additionally, the modern Montessori classroom offers materials presentations and lessons in the areas of Music, Social Studies, Science, and Art. Though the presentation of these areas may occur concurrently, presentations within each are offered sequentially to each child as the children become physically independent, develop the executive functioning skills required to participate in peaceful community, and the capacity to conceptualize of abstract thought.
Sensorial Materials 
heartwoodmontessori.org 