Seasonality appears to have an impact on children's physical activity levels, but equivocal findings demand more study in this area. With the increased use of pedometers in both research and practice, collecting descriptive data in various seasons to examine the impact of seasonality on pedometer-measured physical activity among children is warranted. Therefore, the purpose of this study was to compare the pedometer-determined children's weekday physical activity levels during winter and spring. Participants were first- through fifth-grade students attending two elementary schools in the southern United States. Boys in this study were more active than girls, regardless of season. This finding is consistent with other studies using pedometers and similarly aged children. Although boys were significantly more active than girls during winter and spring, the difference was much less (mean difference = 1,080 steps) during winter. Furthermore, the variability of physical activity levels for boys and girls was lower in the winter. This decreased variability likely resulted from fewer opportunities to be active. Both boys and girls were significantly more active during spring than in winter. Two factors possibly contributed to this finding. The first was the temperature. During the spring data collection, the climate was much more conducive to outdoor physical activity. When the issue of seasonality is examined, the temperature is often the focus; however, it is possible that children would be physically active if they had sufficient daylight hours, even if it were cold. Future research is warranted to examine whether the temperature or daylight hours contribute to lower physical activity levels during winter. (Contains 1 table.)