The focus of this study is the current level of implementation of 18 basic middle school characteristics as perceived by principals of two groups of Ohio public schools, those organized by grades 6-8 and those organized by grades 5-8. Questionnaire responses were received from administrators of 166 of the 208 schools that met the definition of middle schools. Mean scores, variances, and percentages of the maximum possible score yielded by the survey instrument were calculated on each characteristic for each group of schools. Conclusions supported by the findings are that, in general, neither group of schools has implemented the 18 characteristics to a great degree, and that whether a "middle school" houses three or four grades is not significantly related to the level of implementation of the characteristics. The only noticeable differences occurred in the implementation of the characteristics of team teaching, exploratory enrichment studies, and planned gradualism. The grades 6-8 schools showed more advanced implementation of team teaching and exploratory enrichment studies, while the grades 5-8 schools showed more advanced implementation of planned gradualism. The differences are attributed to the fact that grades 5-8 schools often treat their four grades as two entities, whereas grades 6-8 schools consider their three grades as one entity. (Author/MLF)