Benefits of physical activities on child development have been well recognized in the literature. However, limited scientific evidence has been reported on specific activities which could facilitate child motor development in school settings. The present study attempted to examine the effects of a 12-week cup-stacking exercise intervention on motor development for elementary school children. Specifically, influences of the cup-stacking activities were assessed by measuring the changes of selected psychomotor performances between control and experimental groups. Eighty second graders were randomly selected (mean age = 7.1 yr, SD = .36). Thirty-six students participated in a cup-stacking exercise program for 15 minutes every day for 12 weeks and 44 students served as the control with no such an intervention. Three psychomotor performance tests were selected to measure the speed of information processing, upper-limb fine motor control and eye-hand coordination: 1) Finger Choice Reaction Time (RT); 2) Manual Dexterity Test; 3) Rotary Pursuit Tracking Task. These tests were administered at the beginning and the end of the 12-week program for all the participants. A 2 (Group: experimental vs. control) X 2 (Test: pre vs. post) ANOVA with repeated measures on the second factor was conducted on all the dependent variables. Results showed a significant interaction between Group and Test on two-choice RT, F(1, 78) = 4.17, p < .05. The follow-up test indicated that the experimental group had a significant improvement on two-choice RT, however, this was not the case for the control group. Both groups improved their performance on the other two tests, but no group difference was revealed. Physical education curricula should contain meaningful experiences to promote motor development for young students. The cup-stacking exercise program is easy to set up at any school settings and children love to learn and practice the activities. Our data suggest that cup-stacking may be a valuable component of the elementary school physical education curriculum. Keyword(s): exercise/fitness/physical activity, physical education PK-12, research