The use of motor ability tests to achieve sex-fair ability groups should be considered from three standpoints--task specificity, sex differences, and individual learning differences. Motor ability is frequently described as an individual's present ability to perform motor skills. Although several motor ability tests have been constructed for secondary students, many of the tests were separate and gender-specific. The appropriateness of the experimental design, statistics, and methodology employed in the construction of many of these tests is questionable. Several factors mitigate against the use of ability tests for classification purposes. One is the theory that abilities are task specific rather than general in nature. A second factor is the basic gender differences that currently exist on certain dimensions of motor performance, primarily strength and endurance. These differences would probably lead to differences in motor ability test scores and to ability grouping by sex. Differences in rate and amount of student learning reduce the value of classifying students into discrete groups according to natural ability. Motor ability tests have limited value in the classification of secondary students and are not suitable for delineating sex-fair ability groups. (Authors/JD)