The regular certification of arts and science graduates who have not completed the necessary professional education courses has become state policy recently in several states and others are considering it. These four studies provide data on two research questions related to this policy: (1) What, if any, differences in scores on teacher certification tests occur for two groups of teachers: those who have completed teacher education or certification programs, and those who are temporarily certified (arts and sciences majors)? and (2) What, if any, differences exist in on-the-job performance of the aforementioned groups of teachers as measured by evaluation instruments currently in use? The methodology, results, and conclusions of four related studies are presented: (1) a study of scores on the Georgia Teacher Certification Tests for teachers with regular certification and provisional certification; (2) a study of scores on the National Teacher Examinations for teachers with regular and temporary certification in Louisiana; (3) a comparison of the performance of classroom teachers in a metropolitan school district who have graduated from arts and sciences or teacher education programs; and (4) a comparison of performance and test scores for a selected population of teachers with provisional and regular certification in North Carolina. (JD)