Fidget spinners have become popular worldwide, due not only to their popularity with children but also to the mental health claims made by those who advertise them. While a small number of previous research studies indicate that fidget spinners reduce on-task behavior, no research to date has evaluated their effect on student performance. The current study evaluated 3rd grade students to determine whether their performance on 5-min math curriculum-based measures (CBM) changed depending on whether they had access to a fidget spinner. Results indicated that student performance was lower when they were allowed to use fidget spinners than when the fidget spinner was removed. The current study suggests that fidget spinners may cause a deficit in student performance. However, the effect of fidget spinners may actually lessen as the students habituate to the objects.