The purpose of this study was to determine whether physical education lessons focusing on the long jump for elementary school fifth graders would be able to improve their vertical jump velocity. Twenty-eight elementary school fifth graders were instructed in the long jump over 5 lessons. To gain a higher vertical velocity, participants were instructed to pull their swing legs forward at the moment of touchdown and to lean their trunks backward during the jump. Measurements were taken during the first and fifth lessons. To evaluate the jumping motion, the body's center of gravity and segment angles were obtained using a high-speed video camera from a side angle. The main results were as follows: 1) Since vertical velocity at takeoff and jumping distance were both significantly increased, elementary school fifth graders were able to learn to gain a higher vertical velocity. However, the increase in jumping distance was not due to the increase in vertical velocity but rather a decrease in the distance lost during landing. 2) Although post-measurement showed that the swing legs at touchdown were pulled more forward than at pre-measurement, the change in that motion did not contribute to the increased vertical velocity. 3) At post-measurement, the trunk was inclined more backward than at pre-measurement. Therefore, forward rotation of the body was suppressed at takeoff, which increased the vertical velocity. In addition, suppressing the forward rotation of the body strongly contributed to the decrease in distance lost during landing.