The purpose of this study was to examine the impact of school schedule on student achievement and attendance of ninth and tenth grade students in metropolitan area Texas high schools (n = 22) and campus dropout rates. High schools that were analyzed in this study made a transition from A/B block scheduling in the 2003-04 school year to a traditional school schedule in the 2004-05 school year. Academic achievement, attendance rates and dropout rates were gathered through the archived files of the Texas Agency through the Academic Indicator of Excellence System (AEIS). Academic achievement was measured by the Texas Assessment of Knowledge and Skills (TAKS) Reading/Language Arts and Mathematics standardized tests. This study compared the mean scores of ninth grader student achievement, attendance, and dropout rates from the 2003-04 school year to the mean scores of the tenth graders from the same schools from the 2004-05 school year, after the schools converted from an A/B block schedule to a traditional class schedule. Each independent variable was divided into four subgroups; campus mean results, minority student results, limited English proficient (LEP) student results, and low-socioeconomic student results. Students under the A/B block scored significantly higher in reading achievement than when they were instructed the following year under a traditional schedule. Paired sample t-tests were conducted to analyze the data for each subgroup, and showed there was a statistically significance in reading / language arts student achievement scores for all subgroups. Statistical significance was determined with a ninety five percent confidence level (p < 0.05). Statistical analysis revealed varied results in mean scores for math academic achievement and attendance rates, but no statistical significant difference. Comparison of data showed a slight increase in mean scores for dropout rates in traditional schedule, however the results were not significant.