Block scheduling is a newer school scheduling structure, first appearing at the middle school level in the mid-1990's (Juvonen, Le, Kagenoff, Augustine, & Constant, 2004). Middle school advocates have supported block scheduling because research shows it meets the social-emotional and developmental needs of middle school children. Yet, little research on the impact of block scheduling on middle school standardized test scores currently exists. Using a sample of classrooms from a suburban public school in New Jersey, this study sought to compare standardized test scores in math, language arts literacy, and science of 8th grade students before and after the implementation of the block schedule. Twenty-seven one-way ANOVAs (accounting for subject, gender, and special education population) were conducted to assess for significant differences between testing years. Post hoc analyses were also conducted when differences were found. Overall, the study found no significant differences in standardized test scores in the area of science. A planned comparison of pre and post block scheduling standardized test scores revealed statistically significant decreases in mathematics and language arts literacy scores, but a second planned comparison which used data from fewer years revealed only significant decreases in language arts literacy scores which is believed to be a result of the 50% decrease in language arts literacy class time. Varied results by gender were also found. In contrast, special education students' test scores remained the same in all content areas over the seven years. While there are many limitations to the generalizability of these results, it is clear that further research on block scheduling at the middle school level could inform educational practice in these times of high stakes testing. / School Psychology