On the knowledge based society is demanding for competent subjects who can create new knowledge and apply it as well as possess self-directed learning abilities. Even when it comes to instructing underachievers, changes in the systematic education program is being required. Underachievers show difference in learning ability with other students as their grade level increases and this leads to a decline in understanding about what is learned during class. Accordingly, this results in the loss of the desire to learn and is causing underachievement to become more serious. In this paper, arithmetic section was selected amongst all the other sections in an elementary mathematics textbook. In order to minimize the learning deficit of underachievers, recomposition was made with contents and stages appropriate for the instruction of underachievers to develop a self-directed learning model and implement the Scratch game program. As a result of applying the program of this study on underachievers who are in third grade of elementary school, it was analyzed that their competence of arithmetic operation was enhanced and that it also increased their level of interest about learning.