This study, conducted in the Fall of 1981, furnishes statistical data on the vocational self concepts of 12,575 students in grades 7-13. The sample was drawn from all United States regions, controlled for school district size and socioeconomic status, matching the census and Department of Education and National Center for Education Statistics characteristics. The Harrington-O'Shea Career Decision Making (CDM) System was used, assessing occupational preferences, school subject preferences, future plans, work values, and self-reported best abilities and inventoried interests. An analysis of the results showed that females, over different ages, showed inconsistencies between science abilities, preference for science classes, and interests in scientific work settings. Developmentally, female preferences for social-personality types of work environments increased with age. Males consistently progressed in their vocational development, moving into increasingly more realistic values and interests. The critical period for vocational development appears to be during grades 7-9, when male and female variables are comparable. Numerous tables present the results in terms of the CDM System components. (BL)