Aptitude-treatment interaction research is designed to identify significant disordinal interactions between personological variables and alternative instructional programs. This study was designed to investigate the efficacy of the aptitude treatment interaction design to research seeking to identify differential educational payoff of alternative educational programming based on aptitude information. Four aptitude measures were administered to five first grade classes. Following pretesting, curricular interventions were instituted for six months. Class I received word-form configuration training. Class II received visual-perceptual training. Class III received language-conceptual training. Class IV served as a Hawthorne Group in which a resource teacher provided on-going emotional support to the regular teacher. Class V received no specific curricular intervention. Following the intervention phase, six measures were administered as post-tests. Analyses of variance revealed no significant aptitude-treatment interaction in any case. Factors believed to have contributed to the failure to produce significant disordinal interactions include: (1) non-normal distributions on the aptitude measures; (2) an inability to identify discernably different groups on the basis of the aptitude measures; (3) non-parallelism of pretest regression lines; and (4) low reliability for the aptitude and post-test measures. (KM)