The main purpose of this study was to develop predictive expressions for community college curricula, particularly in the vocational areas, that would indicate the probable success of entering freshmen. The study, conducted at San Diego City and San Diego Mesa Colleges during 1967-68, included 2,279 students. The subjects were divided into groups based on enrollment program, sex, and ethnic group. Step-wise regression was applied to 12 predictor variables including: American College Test (ACT) scores, high school grades, educational and economic level of parents, age of students, units of enrollment, and hours of outside employment. The study indicates that: (1) ACT scores do not significantly improve the validity of predictive expressions based exclusively on non-test variables; and (2) expressions developed from the 12 predictor variables have no greater accuracy than the simple prediction that all students will receive a grade point average of 2.00 or better. (Author/CA)