The study traces through path analysis the determinants of algebraic constructs as input in explaining algebraic proficiency of College Algebra students. Results reveal that algebraic proficiency levels of college students from consistent feeder high schools of the study’s laboratory college are not highly differentiated. The majority have below basics algebraic proficiency while the minority has nearly basics. Both proficiency levels imply insufficient preparation for College Algebra coursework and were products of not also highly differentiated algebraic constructs, which were highly significantly traced from high school Algebra teachers’ algebraic constructs as output of their educational background that defined their content – and pedagogical content - knowledge in Algebra. All these traces suggest an informed-College Algebra Curriculum that carries both curative and preventive measures to minimize influx of students with insufficient preparation for College Algebra coursework from consistent feeder high schools.