The study had two main purposes. The first purpose was to determine whether there was any difference in the academic achievement of students receiving their education through a traditional, an alternating eight-block, or four-by-four block scheduled high school in the state of Illinois, as measured by the Prairie State Achievement Exam (PSAE). The second purpose was to determine whether there was any difference in the graduation rates of traditional, an alternating eight-block, or four-by-four block scheduled high schools in the State of Illinois. For the two purposes, socioeconomic status (SES) and type of community were included in the analysis. A questionnaire was sent to every principal from public high schools in the state of Illinois. Of the 637 surveys sent out, 73.3% were returned. ANOVAs were used to compare average PSAE scores in mathematics, reading and science as well as graduation rates. Levels of significance were determined at an alpha level of .05. Tukey/Krammer post hoc tests were used to determine which schedule type(s) were significantly better if the ANOVA showed a significant difference.

While differences were found in average PSAE scores and graduation rates, most of the differences were not significant. Of the 96 possible comparisons, significant differences were found in only 10 occasions. Seven of the significant differences were found in mathematics, two in science, and one in reading. There were no instances of significant difference in graduation rates. The significant differences were found mainly at schools with a high SES, from the suburbs or a combination of the two and from schools with a low SES, from urban cities or a combination of the two.