- Reordered and available shortly
 
           
           
           
          Please note:
Montessori materials are NOT toys, but educational materials. Proper use requires appropriate training.
Montessori materials may contain small, rough, sharp, or other elements that could cause injury or damage if used improperly.
It may therefore only be used by children under the supervision of appropriately trained persons and in an appropriate environment.
Psychoarithmetic is Montessori's most comprehensive text for the development of mathematical thinking and for working on mathematical tasks. The book was written by Maria Montessori after more than 20 years of experience in numerous primary and secondary schools in Europe and America.