Numerous articles and books focus on questions about teaching controversial issues in the classroom, and these controversial issues are on the educational agenda in many countries. The modest goal of this essay is to lay the necessary groundwork for a discussion and study of the goals for teaching controversial issues in schools, in order to examine the practicability of achieving them in the educational reality, and to study possible ways for raising such subjects in the classroom. It refines and adds to the concept of "controversial issues" from a particular, timely, perspective. The rise of "fake news" and "illiberal democracy," including empowered illiberal subgroups in liberal democratic polities demands a reconsideration and new delineation of some of the major tenets proposed by previous scholarship. The delineation that is proposed here moves through three stages. The first stage separates and distinguishes between the controversial issues and the assertions that according to the criteria that logical positivists have coined are meaningful. The second stage proposes the main criterion for defining a topic as controversial, and this is the epistemic-rational criterion, as defined in this essay. The third delineation stage proposes seeing a subject as being controversial if it is currently relevant for social and political life. Moreover, the essay asserts that the result of the examination of these three stages is dependent upon the context -- time and place -- in which the educational act occurs.