Task-related change in physiological arousal is suggested to reflect active involvement with the task. While studies often examine such task-related changes in arousal as averaged across the entire task, the present study focused on temporal changes in arousal during a task. More specifically, we investigated changes in elementary school students’ physiological arousal during an arithmetic task and associations between these changes and students’ mindset, performance on the task, and math grades. We used a person-oriented approach to analyze the tonic electrodermal activity of 86 fourth graders, recorded while they were working on an arithmetic task. With model-based clustering of students’ on-task electrodermal activity, we identified three groups of students with differing temporal dynamics of physiological arousal during the task: Increasing Arousal, Decreasing Arousal and Decreasing and Increasing Arousal. The Decreasing Arousal profile contained more students classified as holding a Fixed Mindset Tendency than would be expected if physiological profile membership and mindset tendency were independent. The Increasing Arousal profile performed better on the task than the Decreasing Arousal profile. No association was found with math grades. These results provide a new insight into individual differences in temporal patterns of on-task physiological arousal.