This study provides preliminary norms and test-retest indices on a brief battery of neuropsychological tests administered to a sample of 60 male and 40 female high school athletes. Forty-eight subjects completed retesting 8 weeks later. Analyses of baseline scores indicate that girls outperform boys on selected measures of processing speed and executive functions [Wechsler Adult Intelligence Scale-III (WAIS-III) Digit Symbol, Trails B, and Controlled Oral Word Association Test (COWAT)]. Test-retest reliability was low and varied widely among the tests. There were no gender differences in test-retest reliability. Reliable Change Indices (RCIs) were computed on the test-retest data for use in clinical interpretation. These preliminary results indicate that caution should be used in interpreting neuropsychological test data from high school athletes. The current findings indicate that separate norms for boys and girls are warranted. Caution should be used in interpreting discrepancies from baseline scores as a result of what may turn out to be poor test-retest reliability in this population.