AFTER ACHIEVING SATISFACTORILY FOR SEVERAL YEARS, SIOUX INDIAN STUDENTS TEND TO SHOW A REVERSAL OF THIS PROCESS AND BEGIN A STEADY DECLINE IN ACADEMIC ACHIEVEMENT. TO STUDY THIS PROBLEM, AN EXPERIMENTAL GROUP WAS SELECTED WHICH INCLUDED THE FOLLOWING OGLALA SIOUX YOUNGSTERS--(1) 164 EIGHTH GRADE STUDENTS FROM SEVEN ELEMENTARY SCHOOLS, AND (2) 159 NINTH GRADE STUDENTS FROM THE TWO HIGH SCHOOLS ON PINE RIDGE RESERVATION. THE CONTROL GROUP CONTAINED 76 WHITE EIGHTH GRADE STUDENTS AND 126 WHITE NINTH GRADE STUDENTS FROM PUBLIC SCHOOLS IN THE SMALL TOWNS CLOSEST TO THE RESERVATION. FOR PROFILE COMPARISONS WITH INDIAN EIGHTH AND NINTH GRADERS AND WITH INDIAN DROPOUTS, 92 SIOUX INDIAN SENIOR HIGH SCHOOL STUDENTS FROM PINE RIDGE WERE TESTED. MEANS AND STANDARD DEVIATIONS WERE COMPUTED ON ALL THE SCALES FOR COMPARISONS AMONG THE VARIOUS GROUPS, AFTER WHICH "T TESTS," ANALYSIS OF VARIANCE, AND SCHEFFE TESTS WERE UTILIZED TO DETERMINE SIGNIFICANCE AND TO LOCATE DIFFERENCES. WHEN ANALYZING ACADEMIC ACHIEVEMENT IT WAS FOUND THAT THE INDIAN GROUP FELL SHARPLY BEHIND THE WHITE GROUP AT THE EIGHTH GRADE LEVEL. THE TOTAL INDIAN GROUP REVEALED GREATER PERSONALITY DISRUPTION AND POORER ADJUSTMENT WHEN COMPARING THE PSYCHOLOGICAL VARIABLES OF REJECTION, DEPRESSION, ANXIETY, AND TENDENCIES TO WITHDRAW, PLUS SOCIAL, SELF, AND EMOTIONAL ALIENATION. (ES)