This brief third volume of a three-volume study addresses in more detail several analytical issues raised in the first two volumes. The overall study involved research on the former New Castle County (Delaware) School District--reorganized into four districts in 1981--to discover whether the 1979-82 overrepresentation of minority students (mostly blacks) in suspensions, special education, and lower academic groupings resulted from discriminatory practices. Using data from the first two volumes, this part of the study compares the effects on suspensions of variables besides race, including student socioeconomic status, sex, and class rank as well as school enrollment size and percentage of minority students. Analysis using ratios and percentages indicates that not only minority students, but also males, high school students receiving Aid to Families with Dependent Children, and senior high school students in lower class ranks, are all overrepresented in suspensions. Further analysis using Pearson's correlation coefficient reveals no statistically significant relationships between minority suspensions and either school size or percentage of minority students. The author recommends that the schools and the community work on the entire area of discipline rather than on discipline in relation to any one factor. (RW)