Block scheduling constitutes one of the major types of restructuring considered by school administrators seeking to improve student performance. The relationship between two school schedules--the seven-period A/B block and the seven-period traditional schedule--and achievement of students in grade 11 was examined. Comparisons showed no significant increase in students' test scores over time associated with the alternating schedule. Although school leaders may find some improvement in the initial year of implementation, improvements may be negated by decreased improvement rates in later years. A statistical analysis bears out more general literature on the subject.