RESUMEN
The purpose of this study was to collect normative data on and to assess the clinical usefulness of scales designed to measure the quality of children's ability to perform three bilateral motor coordination tasks: jumping jacks, symmetrical stride jumps, and reciprocal stride jumps. One hundred children, aged 5 to 9 years, were tested according to the scales developed for this study. Results indicated that scores tended to increase with age and that sex differences were not significant. Jumping jacks were found to be the most reliable and the easiest of the three tasks. Reciprocal stride jumps were the most difficult. Quality of performance was assessed, and the number of jumps in a 10-sec trial was recorded for each age. The data from this study may be useful in comparing the performance of children with motor deficits to the performance of normal children of the same age.