The purpose of this quantitative correlational research was to investigate to what extent 2007 performance of third grade students who had been retained in 2006 for failing to attain proficiency on the Reading and Mathematics Florida Comprehensive Assessment Test (FCAT) predicted their performance in 2010 on the sixth grade Reading and Mathematics FCAT. There was no theoretical foundation for retention and the study was based on grounded research on benefits and detriments of grade level retention. The researcher answered two questions regarding the ability to predict student success in sixth grade on the Reading and Mathematics FCAT based their performance after retention. The researcher analyzed secondary data available for 108 students from a mid-sized urban school district in Florida using simple linear regression. The results showed that test scores attained after the students repeated third grade significantly predicted their performance on both the Reading and Mathematics FCAT when they were in sixth grade, F(1, 105) = 26.03, R[superscript 2] = 0.199, ß = 0.40, p < 0.001 for reading and F(1, 105) = 72.27, R[superscript 2] = 0.408, ß = 0.68, p < 0.001 for mathematics. The positive impact of improved performance in third grade after retention on the sixth grade performance was stronger in Mathematics, R[superscript 2] = 0.408, than in Reading, R[superscript 2] = 0.199. These results provided empirical evidence that students' performance after retention in third grade was directly related to those students' performance in the sixth grade, and its long-term impact supports the effectiveness of grade level retention policies. [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.]