The lack of an adequate and organized transfer of steps in the subtraction process results in a learning difficulty of this operation in elementary school. The objective of this study is to show how the use of a digital educational resource can help improve the mathematical performance of children with dyscalculia. In particular, how the systematic application of a digital resource improves the resolution of subtraction, compared to the resolution of such operation without it. The study was carried out by applying a learning sequence of systematized subtraction and adapting it to the specific difficulties of the student and then selecting a motivating digital resource. Our results suggest that the use of this resource has made outstanding contributions to the achievement of this mathematical operation. It is recommended to carry out studies in this line to contribute to improving the learning process of school children with these difficulties.