There are many advantages and disadvantages of ability tests for sex-fairness. Several types of assessment criteria for sex-fair ability grouping could be used in fitness-related activities in the curriculum. Health-related physical fitness tests, designed to measure an individual's health fitness and provide for individual improvement, are not conducive to sex-fair ability grouping. However, health-related fitness test results are appropriate for conditioning-type activities. Skill/activity testing methods for sex-fair ability grouping would be effective in some activities, such as swimming and gymnastics, but not in softball or football. Motor ability testing appears to be the best method for general placement of students in sex-fair ability groups in most activities. Skill/activity and motor ability test results are suitable for sex-fair ability grouping in team and individual/dual sports. Few results of any of the three types of tests are applicable to sex-fair ability grouping in rhythms/dance and recreational activities. Ability grouping methods appropriate to programs in the large high school, the small junior or senior high school, and a flexible, modular-scheduled school differ because of the number of students, diversity of student abilities, number of physical education courses and electives, and time schedules. Techniques recommended for sex-fair coeducational classes would involve: (1) efforts to improve girls' skill and fitness levels; (2) review of physical education goals and objectives; (3) sex-fair curriculum and instruction; (4) balance of males and females in coeducational classes; (5) nondiscriminatory behaviors and attitudes; (6) use of several ability grouping methods; (7) structured learning experiences; (8) safe learning condiditons; (9) fair game play; and (10) individualized instruction. (Author/JD)