The purpose of the study was to examine the impact of a teacher's preparation program on the academic achievement of eighth grade students in the areas of mathematics, reading, science, and social studies. Prior to the implementation of the No Child Left Behind Act (NCLB) in 2001, the majority of classroom teachers earned their teaching certificate through traditional university teacher preparation programs. The NCLB component requiring a highly qualified teacher in every classroom was a precursor to the rapid growth of alternative teacher preparation programs. The ex-post facto, causal-comparative study was designed to examine the impact of a teacher's preparation program on the academic achievement of 133 eighth grade students on standardized state assessments in the areas of mathematics, reading, science, and social studies. Data from the school district included raw scores for each of the State of Texas Assessment of Academic Readiness (STAAR) reporting categories in these four academic areas as well as demographic data. Results showed that in mathematics, students of alternatively prepared teachers outperformed students of traditionally prepared teachers in geometry and spatial reasoning, and probability and statistics. In reading, there were no statistically significant differences between the two groups on the basis of any of the outcome measures. In science, students of alternatively prepared teachers outperformed students of traditionally prepared teachers in matter and energy. In social studies, students of alternatively prepared teachers outperformed students of traditionally prepared teachers in history, geography and culture, and economics, science, technology, and society. Student achievement is a critical component of the success of a school or district. Students who are well prepared for rigorous postsecondary education will be able to meet the demand for a skilled and educated workforce in challenging careers. Failure to prepare students is a major cause of the loss of millions of jobs to other countries due to the search for educated workers. The potential impact of a teacher's preparation program on academic achievement of students is potentially valuable information, as educational outcomes strongly affect economic growth and the distribution of income. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]