The purpose of this study was to conduct a concept analysis of middle school American history textbooks to determine the extent to which the substantive concepts developed by the Syracuse University Social Studies Curriculum Center are included. Each of the eighteen concepts was modeled and applied to three textbooks in a concept analysis system. The two sub-problems of this study concerned the number of Syracuse substantive concepts included in each textbook and the degree of treatment--major and minor--that each concept received in the textbooks. Previous research indicated no studies had used a concept analysis system based on model building, had analyzed the Syracuse concepts or had modeled the individual concepts used in the analysis system. The literature review focused on four areas: the development of the Syracuse Center and its concepts, concepts and concept development, model building and textbook analysis. The concept analysis system employed the following main procedures; 1. Read each textbook page by page. 2. Determine the concept which is the major focus of the chapter sub-heading, sub-sub-heading or illustration. 3. Look for the possible main categories, sub-categories and elements included in the central concept. 4, Make necessary codings on the Concept Analysis Data Work Sheet. Four conclusions were reached by this study. First, the concepts received a lack of comprehensive coverage in the textbooks. Second, most of the central concepts were included in the textbooks, but they were not reinforced after the initial presentation. Third, pictures were the most often selected illustration in the textbooks. They were generally used as reinforcers of the central concept. Fourth, the previous research, although unlike this concept analysis system, had indicated an inadequate inclusion and treatment of the broad concepts investigated. This study tended to support these previous research findings. The findings of this study can be used by teachers to improve concept teaching or development with students, by writers of conceptoriented materials as a tool for analyzing their textbooks or other materials for concept presentation, omission and areas of needed concept reinforcement, by curriculum committees as an evaluation instrument for determining the conceptual adequacy of textbooks and other materials considered for adoption, and by the educational profession in considering the potential of model building as a tool of curriculum design, development and evaluation, In addition, suggestions for further research are presented. / Ed. D.