The purpose of this research is to evaluate the effectiveness of the area (homogeneous) scales of the Navy Vocational Interest Inventory (NVII) as predictors of Class "A" school achievement and as measures of rating differentiation by comparing specific occupational scales with more general interest measures--the NVII area scales. The NVII was administered experimentally to samples of incoming students at six Class "A" schools varying widely in curriculum and to a sample of students in the Submarine School. In addition to NVII area scales, scores on Basic Test Battery (BTB) subtests were available for men in each school. Multiple correlations were computed, thus allowing validity comparisons of the BTB in predicting Class "A" school achievement to be made with and without the addition of NVII area scales. These multiples were compared to multiples obtained using occupational key scores. Average area scale profiles of the various occupational groups were compared to those obtained using occupational key profiles. The area scales were found to be as effective as occupational scales in differentiating the interest patterns of men in various schools and to contribute significantly to the prediction of Class "A" school achievement. It was concluded that the differences between the two types of scales were not substantial. (Author)