A study was conducted in 2021 in Switzerland (Canton of Vaud) to evaluate two computer-based learning programs Calcularis 1 and Matheros 2 to help students improve their performance in calculation. Calcularis was especially designed to support students with mathematical learning difficulties. Then, our study focuses on the evaluation of the effect of Calcularis on the mathematical learning skills for students with mathematical learning difficulties in ordinary school context. We observed that Calcularis could allow a better progression compared to Matheros in calculation, number-line estimation task for students with mathematical learning difficulties.