This is a quantitative research study using archival data to focus on the achievement of Gifted & Talented students in two South Carolina public school districts. The researcher used an open cohort comparative research design for this study. This study attempted to find if differences in student performance existed between students labeled as Gifted & Talented in South Carolina based on their model for instruction. The researcher used their Palmetto Assessment of State Standards (PASS) test scores in English Language Arts (ELA) and math achievement scores and compared them to the students' placement in special class model Gifted & Talented classrooms or traditional pull-out G/T classrooms. This study took approximately one and a half years and used scores from the 2009, 2010, and 2011 academic school years. The dependent variable was the scale scores gathered from the PASS tests during those years. The independent variable was the grouping method. Other intervening variables include school, district attended, socioeconomic status, ethnicity, and gender. [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.]