NEW INTELLECTUAL APTITUDES WERE INVESTIGATED TO DETERMINE TO WHAT EXTENT THEY INFLUENCE ACHIEVEMENT IN NINTH-GRADE ALGEBRA AND GENERAL MATHEMATICS COURSES. TESTS AND CRITERIA WERE COMPLETED FOR APPROXIMATELY 400 STUDENTS IN THE NINTH GRADE. THEY WERE ENROLLED IN ONE OF FOUR MATHEMATICS COURSES AND ADMINISTERED ACHIEVEMENT EXAMINATIONS UPON COMPLETION. THE ROLES OF SEPARATE FACTORS WERE INFERRED FROM THE BETA WEIGHTS OF THE EQUATIONS. SOME OF THE CONCLUSIONS WERE THAT STANDARD TESTS DO AS WELL AS FACTOR TESTS IN PREDICTION, AND THAT COURSE LEVEL INFLUENCES THE FACTORS INVOLVED. FURTHER RESEARCH IS SUGGESTED TO STUDY APTITUDE WITH A BROADER SAMPLING OF INTELLECTUAL ABILITIES. (RS)