Examined were relationships among various verbal and nonverbal personality scales purporting to measure extent to which an individual behaves as if he, or the environment, controls events. Also investigated were developmental trends related to this internal-external dimension of personality and its relation to academic achievement of the educable mentally retarded (EMR). Subjects were 215 EMR children (ages 9-15 years, IQ range 45-82), who were administered a battery of six tests. The hypotheses that there would be a significant relationship among the personality measures at all age levels across settings, and that there would be a developmental trend across the age span involved, moving from an external to internal frame of reference as age increased, were not sustained. It was concluded that internal and external dimensions of personality play a minimal role in the academic achievement of EMR students as compared to the roles played by MA and CA. (See ED 038 779, EC 003 339 for project interim report.) (Author/KW)