This study reviewed in what theoretical contents concerning class and stratum related to social inequality. Through a theoretical review, it was found that not only traditional hypotheses about social inequality but also new theoretical arguments, which have been developed based upon the old ones, have been so diverse that those arguments need to be noted, considering complicated stratum phenomenon of today's modern society. From analyzing the high school social and cultural textbooks, it was found that function theory, conflict theory, and class and stratum are presented as main viewpoints and criteria. However, in the present textbooks, class and stratum are mentioned only to an extent of briefly describing the theoretical viewpoints, which gives no room for learning contents. Also, it is hard to expect guide and facilitation for specific inquiry learning of various class and stratum due to little consistency in content organization of the textbooks. To begin with, the existence of the middle-class between the classes or middle level is not specifically clarified. Second, the essence or purpose of the education about the classes or hierarchy is also not specified. Third, it is not mentioned what the historical view is, which becomes the theoretical foundation of Marxism and Weberian Paradigm. Moreover, there are no instructions about the theories of a variety of classes and hierarchy. Lastly, the limitations of Marxism and Weberian Paradigm cannot be recognized. Therefore, this study demands that a clear description of Marx's class theory and Weber's view of stratum should be given, and that learning contents and methods should be supplemented in order that new theories on social inequality related to class and stratum, which are based on traditional ones, and related criticism of the class theory can be looked into in perspective in school.