What are the basic things that compose curriculum, and what are the questions that may be posed about these things? Joseph Schwab's conception of curriculum is used to introduce a scheme of questions concerning the nature, elements, and practice of curriculum. Formulations of questions by other curriculum theorists are reviewed and analysed in light of this scheme, and the various uses of such questions are described. How far the questions prove to enhance thinking and acting in the domain of curriculum is the ultimate criterion of the usefulness of the questions. The answer to this final test question, as to the others, is to be found in the circumstances of practice. (Contains 2 tables.)