This study examined the effect of a 6-week school-based pedometer intervention for children. It compared the number of step counts between group- and individual-based step goal conditions over time, and compared the number of goal attainments between the two step goal conditions by physical activity levels. Ninety-nine 4th-grade students’ (50 boys, 49 girls) data were analyzed. Overall step counts continued to increase over time, increasing about 19% from baseline. Different step goal conditions produced similar effects on children’s physical activity levels across all time points. The number of goal attainments was higher for low active children with individual-based step goals than those with group-based step goals. Using pedometers in school is promising for enhancing physical activity in children.