The Purpose of This Investigation : The purpose of this investigation is to determine the comparative validity of high school bark's and mental tests scores in predicting success in college. Realizing that marks are relative, and that there are no definite universal marking standards in our educational system, the data for a study of this kind may lack the technical exactness which may characterize researches in some other fields, hut a serious effort is made throughout this study to follow scientific procedure insofar as this type of research can he performed scientifically.