  To contrast the phenomenon of false positives in the diagnoses of dyscalculia
in Italy, among 3rd grade children, a 3-year project (2011-2014), built upon a
collaboration between psychologists and mathematics educators, was carried out.
Within the project specific teaching strategies for preventing and addressing
learning difficulties in arithmetic arising at the beginning of primary school
were designed and tested in schools nation wide. This paper presents the
project's background and the theoretical foundations of the didactical material
designed, providing also some examples. In particular, prototypical examples
will show how the activities, grounded within a kinesthetic-tactile and
visual-spatial approach, are designed to lead to students' interiorization of
part-whole relations, and to their thinking about multiplication through
structured diagrams. Qualitative data confirming effectiveness of the proposed
didactical strategies will also be discussed.
