High schools around the nation are attempting to find a solution to the "9th-grade bulge," and the ever-growing systematic problem of 9th grade retention. The purpose of this study was to investigate the impact of the daily bell schedule on ninth-grade student achievement and overall school performance. A mixed method, sequential explanatory design was utilized to compare the two most common bell schedules; 7-period and 4 x 4 block. The quantitative portion of the study examined 9th grade achievement on the Georgia Milestones End-of-Course (EOC) Assessments and the overall school performance was measured by the College Career Performance Index (CCRPI) and its components. Twelve principals were interviewed for the qualitative section to gain more insight on the quantitative results. [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.]