Abstract: | Different instructional programs were developed for three mathematics aptitude item formats to determine the relative susceptibility of each to special instruction. Subjects were male and female high school junior volunteers in 12 schools. In the seven weeks between a pre- and posttest, experimental Ss received 21 hours of instruction for one of the three formats; control Ss received no special instrucion. Each of the three formats was found susceptible to instruction directed toward it. The complex formats were most susceptible. Female Ss were slightly less able mathematically at the outset and benefited less from instruction than males. Mean gains of nearly a full standard deviation for groups instructed for the complex formats were considered to be of practical consequence. |