Positive findings regarding integrated curriculum in the classroom setting (Chen & Yang, 2019; Kurt & Pehlivan, 2013; Vars, 1996) and movement integration during the school day (Donnelly et al., 2009; Duncan, Birch, & Woodfield, 2012; Mahar et al., 2006; Reed et al., 2010), suggest a movement-based setting, such as physical education, could be another site for successful integration. Of the few empirical articles integrating classroom content into physical education, two quantitative studies provided guidance for the present study (Cecchini & Carriedo, 2020; Derri et al., 2010). These studies found that integration in physical education resulted in increases in academic performance. The purpose of the present study was to examine the effects of integrating mathematics into physical education. One-hundred and thirty-two fourth grade students from four physical education classes at two schools participated in this study. In-tact physical education classes were randomly assigned to intervention and control groups. In this eight-week study, ten-minute mathematics activities (Cosgrove & Richards, 2019) were integrated into the intervention group's physical education classes, while the control group participated in regular physical education. Data collection included assessments of mathematics performance, mathematics attitudes, mathematics perceived competence, athletic perceived competence, and physical education interest. These data were collected pre- and post-intervention from both the intervention and control groups. Data were analyzed using mixed nested ANOVA and independent samples t-test. Results showed that across all measures of mathematics performance students in both groups significantly improved from pre- to post-intervention. Significant differences based on the interaction of time (pre-/post-test) and group (intervention/control) were only evident in mathematics unit assessments and not present in the global measures of mathematics performance of mathematics grades and mathematics standardized test scores. The intervention group reported greater situational interest in physical education than the control group. No significant differences were observed across other measures of mathematics attitudes, mathematics perceived competence, and athletic perceived competence. These findings add to the growing body of literature of integrated curriculum in physical education. [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.]