The current research aims to identify the effectiveness of a computerized program in developing mathematical skills among the first cycle students in basic education schools in the Sultanate of Oman. The two researchers used the quasi-experimental approach on an intentional sample consisting of (40) male and female students at Al Kawakeb School for Basic Education (1-4). Two of the basic fourth-grade classes and then randomly distributing them into two groups, one is experimental (20) male and female students who followed the computerized interactive program, and the other is (20) male and female students followed the traditional way. On the other hand, its reliability has reached (0.81), and the results of the research have concluded that there are statistically significant differences at the level (0.05) between the mean scores of the experimental and control groups in mathematical skills in post-application in favor of the experimental group. The computerized interactive program has achieved a significant impact, as it was ETA square ≥ 0.14 in all mathematical skills, and the program achieved a degree of effectiveness ≥ 1.2 according to the modified gain factor for BlackBerry in developing mathematical skills for fourth-grade primary students. In light of previous results, the researchers recommended the need to pay attention to interactive computerized programs in providing educational material because of its positive impact in the development of the skills of pupils, the computerized program prepared by the researchers by the competent authorities in the burdens of Education in the Sultanate of Oman and the adoption.