The purpose of this study was to determine if there were a significant difference in math and reading academic achievement scores between eighth-grade students attending year-round calendar schools and eighth-grade students attending traditional calendar schools based on the TCAP. In addition, this study investigated math and reading achievement scores for eighth-grade students identified as economically disadvantaged, minority, and special education attending year-round calendar schools and traditional calendar schools based on TCAP. Specifically, the research hypotheses explored were: (a) There is a significant difference in math and reading achievement scores as measured by TCAP between eighth-grade students attending a year-round calendar school and eighth-grade students attending a traditional calendar school. (b) There is a significant difference in math and reading achievement scores as measured by TCAP between eighth-grade students identified as regular education, minority, special education, and economically disadvantaged attending a year-round calendar school or a traditional calendar school. Students who attended year-round calendar schools scored significantly higher on their TCAP scores in reading than students who attended traditional calendar schools. Students who attended year-round calendar schools achieved higher scores in reading comprehension and fluency due to more time allotted for reading remediation. Regular education and minority students differ significantly in math for year-round schools and traditional calendar schools. Minority students who attended traditional calendar schools scored lower on the TCAP in math than regular education students who attended year-round calendar schools. Minority students attending year-round calendar schools scored significantly higher in number and operations and algebraic thinking than minority students attending traditional calendar schools. Special education students scored significantly higher in number and operations and measurement than special education students attending a traditional calendar school. Economically disadvantaged students scored significantly higher on the TCAP in math than special education students attending traditional calendar schools. Economically disadvantaged students attending year-round calendar schools scored higher in geometry and problem solving than special education students attending a traditional calendar school. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]