Studies on math learning programs are lacking that consider a wide set of outcome variables, and students' practice behavior. Therefore, we investigated whether an adaptive arithmetic learning program fosters students' math performance (addition and subtraction), math self-concept, and a reduction of math anxiety, and how practice behavior (practiced tasks and practiced weeks) affect the investigated variables. We used a pre-post control group design with a total of 366 fifth grade German students. Randomization took place on the class level. Students in the experimental condition used the program for 22 weeks. Math self-concept only improved in the experimental group. Students' subtraction performance improved as a function of practiced tasks, and addition performance improved as a function of practiced weeks.