The American high school schedule of single-period classes has remained mostly unchanged for over one hundred years. In response to societal changes and reform movements, the secondary school schedule is receiving renewed attention. Block scheduling, the use of extended periods of time for learning, is one response to school restructuring in Virginia and throughout the nation. In Virginia, the 7A/B block schedule is used by 23.3% of the high schools. Although advocates have convinced school boards to adopt this schedule, there is little hard data available to assess its efficacy. In this study the relationship between two types of schedules(7A/B block and 7-period traditional) and student achievement at the eleventh grade was examined. No differences were found between the two schedules for achievement as measured by the subscales of the eleventh grade Tests of Achievement and Proficiency. / Ed. D.