The study examined the effectiveness of a 4-week classroom-based, technology-assisted physical activity break program on elementary students' reaction time, response inhibition control, and mathematics performance. Participants included 40 (8-9-year-old) elementary school students located in the mid-south United States (US) who were cluster-randomised and allocated to the intervention (n = 19; 14 boys, 5 girls) and school-as-usual (n = 21; 17 boys, 4 girls) groups. The intervention group played FitNexx active video game 10-minutes daily before mathematics classes. Data collection included mathematics performance test and cued Go/No-Go test for inhibitory control and reaction time. The findings showed that the intervention had a positive effect on students' reaction time (F[2,39] = 29.98, p < 0.001, n[superscript 2] = 0.45) and response inhibition control (F[2,39] = 21.02, p < .001, n[superscript 2] = 0.36). No effect was found on mathematics performance (F[2, 35] = 0.51, p = 0.479, n[superscript 2] = 0.02). The study contributes by providing evidence on how technology-assisted classroom activity breaks can produce positive, chronic cognitive response.