The aim of this study was to clarify the effect of tactical training in the general tactical ability of ball games based on the “Ball School” program for young children. The tactical task in this study required the “positioning ability on the field” in which children moved on the field while avoiding two consecutively moving fitness balls. In this study, the position coordinates of the child and the two balls calculated by the 2-dimensional DLT method were used. Then, the position of the child, the movement distance/speed of the child, and the distance/angle between the ball and child were compared before and after the tactical training. The main results were as follows: 1) after training, the frequency of children’s movement increased toward the central area in the field, 2) In the ball holding phase after training, the children’s movement speed improved by about 0.2m/s on average, and the angle between the child and the two balls improved by about 20 degrees on average, 3) These results suggest that the “Ball School” coaching style, which emphasizes implicit learning, improved the tactical behavior of “positioning on the field” in young children.