The problem that inspired this study is that Turkish students' mathematics rankings on global exams such as The Program for the International Students Assessment (PISA) and Trends in International Mathematics and Science Study (TIMMS) had been below the average for many years, a problem that may have rooted in children's early experiences with mathematics. The purpose of this quantitative pretest posttest quasi-experimental control group study was to determine the effect of computer-programming classes with Code Studio on mathematics scores of preschool students. Siemens's connectivism theory for the digital age formed the foundation for this research. A single research question regarding the effect of computer coding classes on mathematics scores of preschool students over one academic year guided this study. The sample of this study consisted of randomly selected 128 students' mathematics scores who are attending two preschools. One of the preschools implemented computer programming classes with Code Studio, experiment group and the other did not, control group. The dependent variable (posttest) was mathematics scores of the both groups taken in June. Pretest mathematics scores was the covariate and was administered in September of previous year. An ANCOVA test was used to analyze the data. The results indicated a statistically significant difference in mathematics post scores in favor of preschool students who were taught computer coding compared to students who were not taught computer coding. The social change implication of this study is that widely adopted early coding instruction may increase early mathematics achievement, which may lead higher mathematics achievement for longer term. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]