This report concerns the preliminary tryout of tests intended for use in comparative prediction at the ninth-grade level. A nine-hour battery of pure-factor aptitude tests and of interest measures was given to students in all grades of the Middlesex and Essex County, New Jersey, Vocational and Technical High Schools. The ninth-grade data were used for internal test analysis. This report discusses the follow-up done with the data for the eleventh grade, twelfth grade, and special graduate classes. The follow-up included the gathering of school shop grades, job ratings by employers a half to one year after leaving school, and scores on satisfaction with the trade entered. The validity study shows that, among the 30 scores validated, there are a considerable number of validity coefficients suitable for comparative prediction for success in the various school shop courses. The validity of the tests is less good for the job criteria.