Montessori believed that the learning environment was as important as the learning itself. Effective learning occurs in a structured environment. A well-prepared environment should include tables, chairs, shelves, cabinets, and should be large enough for the size and needs of the children (Week 3, Study Notes, page 24). He also believed that handicapped, hearing-impaired and mentally deficient children also needed a special environment for their special education. Materials are very important in the Montessori method, that's why she created a series of materials. The materials in this set are: a wooden set, could be cylinders and blocks. Ten pink blocks of graduated sizes, ten red rods and ten brown wooden prisms, fabrics and boards of different texture, weight and color, wooden puzzles, various geometric shapes glued on papers, wooden boards with pentagram lines, musical bells and wooden discs. All this material helps children's sensory development (Week 3, Study Notes, page