COUNSELING TREATMENT METHODS WERE EVALUATED TO DETERMINE THEIR EFFECTIVENESS IN IMPROVING ACADEMIC AND PERSONAL ADJUSTMENT OF UNDERACHIEVING HIGH SCHOOL STUDENTS. THE PARTICIPANTS INCLUDED OVER 200 MEASURED UNDERACHIEVERS FROM GRADES 10-12 AND 16 COUNSELORS. THE STUDENTS WERE RANDOMLY ASSIGNED TO ONE OF FIVE TREATMENT CONDITIONS--(1) INDIVIDUAL COUNSELING, (2) GROUP COUNSELING, (3) SMALL GROUP STUDY SKILLS INSTRUCTION, (4) INDIVIDUAL AND GROUP COUNSELING COMBINATION, AND (5) A CONTROL CONDITION OF NO TREATMENT. TO ASSESS CHANGES OCCURRING BY EACH CONDITION, SEVERAL MEASURING INSTRUMENTS WERE USED. AN ANALYSIS OF VARIANCE WAS EMPLOYED TO EVALUATE TREATMENT EFFECTS. SIGNIFICANT DIFFERENCES WERE INDICATED ON THE EFFECTIVENESS OF DIFFERENT TREATMENTS. STUDENTS IN THE INDIVIDUAL COUNSELING AND STUDY SKILLS GROUPS IMPROVED MORE THAN THOSE IN THE OTHER GROUPS IN GRADE POINT AVERAGE AND STUDY HABITS. ON THE CRITERION OF PERSONALITY CHANGE, THERE WERE NO SIGNIFICANT DIFFERENCES BETWEEN TREATMENTS. A NEED FOR HIGH SCHOOL COUNSELORS TO FIT TREATMENTS TO GOALS AND NEEDS OF INDIVIDUAL STUDENTS WAS INDICATED. (RS)