Adults benefit more from external focus than internal focus when learning a new motor skill. Because learners from different age groups use different learning strategies, the purpose of this study was to investigate whether the effect of varies attention focus between children and adults. Twenty children and eighteen adults were randomly assigned to internal and external focus of attention practice groups. Dart throwing done toward a static target, participants performed 50 acquisition trials, 20 retention trials, and 20 transfer trials. The results indicate that focus of attention varied between children and adults in accuracy and variability of the acquisition, retention, and transfer phase and in accuracy of the transfer phase (P<0.05). This study suggests the need to develop appropriate selection criteria of participants according to their age. Physical therapists working with children should perhaps direct the client's attention internally; however, further study is needed.