In Montessori classrooms the materials are also known as Didactic Materials. In a typical classroom they may be referred to as manipulatives. Didactic materials are unique in that not only are they manipulative but they must include these criteria:
They isolate one point of interest or concept.
They lead students from a concrete example to an abstraction.
They lead students from an unknown concept to a known one.
They are made precisely, and are to be of natural products and kept in excellent condition.
They are to be presented on the shelves in a way that they ‘call to the child’.
They are presented first by the Directress often using a three period lesson to model how the material will be used by the student when practicing.
The student is to practice and then through repetition show mastery.
They have a ‘control of error’ which allows the student to learn from use rather than the teacher.
The directress observes the student using and practicing material and then can determine the student’s level of independence and mastery authentically.