Teaching and learning concrete and theoretical arithmetic through technology

In this work we analyse the role of technology in the solution of theoretical and concrete arithmetic problems. In particular, we consider the role of ARI-LAB 2 system that makes available mediating tools (Microworlds) for the construction of solution processes for these two types of problems. Microworlds of Ari-Lab-2 allow the student to manipulate interact with computational objects receiving various kinds of feedback. We present some results concerning the use of ARI-LAB-2 Microworlds for the development of competencies both in concrete and theoretical arithmetic and we discuss the pedagogical and educational potential of this system.