The purpose of the study was to determine if standardized math test scores improve by administering different types of exercise during math instruction. Three sixth grade classes were assessed on the Measures of Academic Progress (MAP) and the Minnesota Comprehensive Assessment (MCA) standardized math tests during the 2012 and 2013 academic year. The MAP standardized test was given at the beginning and end of the academic year. The MCA test was given every spring. The classes used the same math curriculum. Each class had a different math teacher, but each teacher taught the same class all year. One math classroom (n = 23) did no physical exercise during instruction, another (n = 29) conducted two 5-min physical activity breaks during each math period, and the third math classroom (n = 29) always sat on stability balls. A one-way ANOVA was computed for both MAP and MCA improvement scores across the three classrooms to determine if exercise affected standardized math test scores. MAP improvement scores were significantly higher for the class that sat on stability balls (mean = 11.6, SD = 6.9) when compared to the sedentary class (M = 5.5, SD = 7.0). MCA improvement scores were also significantly higher for the stability ball class (M = 104.9, SD = 19.7) when compared to the class that conducted activity breaks (M = 92.6, SD = 7.4). The results indicate that stability balls may provide better focus for learning than short duration vigorous physical activity or no physical activity during math instruction.