In 1994, National Education Commission on Time and Learning published Prisoners of Time, which encouraged schools to direct their attention on learning rather than time and stressed block scheduling to be an appropriate means of assisting teachers in engaging students in active instruction. Since the National Education Commission on Time and Learning advocated for block scheduling to replace the traditional schedule, additional mandates by No Child Left Behind (NCLB) have encouraged schools to improve student achievement and show adequate progress in graduation and attendance rates. The purpose of this study was to determine the long-term effects block scheduling has in the high school setting beyond the first 4 years of implementation by analyzing students’ ACT scores, student attendance, and high school graduation rates from two high schools in rural West Tennessee school districts. The sample was comprised of students who attended one of two high schools during the 1996–1997 school year or between the fall of 2000 to spring of 2009. Specifically, the research hypotheses explored were: (a) There is a significant longitudinal difference between the academic achievement of students on a block schedule and the academic achievement of students on a traditional schedule as measured by composite ACT scores. (b) There is a significant longitudinal difference between the graduation rates of students on a block schedule and graduation rates of students on a traditional schedule. (c) There is a significant longitudinal difference between attendance rates of students on a block schedule and attendance rates of students on a traditional schedule. In testing the hypotheses, it was found that student achievement was not significantly different as measured by students’ ACT composite scores at the two schools. However, although not significant, the longer the treatment group stayed on the block schedule, the less of a difference was found between the academic achievement of students in the two schools. Graduation rates were not significantly different between the two schools. On the other hand, the school on the block schedule did have significantly higher attendance rates. Further implications of the results are discussed.