APTITUDE MATURATION RESEARCH COMPLETED IN 1959 MADE IT POSSIBLE TO EXTEND THE USE OF THE GENERAL APTITUDE TEST BATTERY (GATB) TO EDUCATIONAL VOCATIONAL COUNSELING OF NINTH AND 10TH GRADERS. IN AN EFFORT TO EXTEND ITS USE FURTHER, THIS STUDY WAS MADE TO DETERMINE THE EXTENT TO WHICH THE OCCUPATIONAL TEST NORMS VALIDATED ON ADULT SAMPLES PREDICT THE SUCCESS OF HIGH SCHOOL STUDENTS IN VOCATIONAL COURSES. A TEST COMPOSITE DEVELOPED IN 1953 WAS GIVEN TO 70 NINTH GRADE STUDENTS ENROLLED IN A VOCATIONAL PRINTING COURSE PRIMARILY CONCERNED WITH HAND COMPOSITION. THE STUDENTS WERE TESTED WITH THE ENTIRE GATB AT THE TIME OF SCHOOL ENTRY. UPON COMPLETION OF THEIR FIRST YEAR OF THE PRINTING CURRICULUM, THEY WERE RATED BY COURSE INSTRUCTORS ON A 12-ITEM DESCRIPTIVE RATING SCALE SPECIFICALLY DESIGNED FOR THE STUDY. THE CORRELATION BETWEEN THE APTITUDE NORMS, ADJUSTED ON THE BASIS OF APTITUDE MATURATION, AND A DICHOTOMIZED CRITERION OF INSTRUCTOR RATINGS WAS SIGNIFICANT AT THE 0.01 LEVEL, THE SAME LEVEL AS THAT IN THE 1953 STUDY. THIS DOCUMENT APPEARED IN "VOCATIONAL GUIDANCE QUARTERLY," AUTUMN 1965. (JK)