Ethical reasoning is a way of thinking about issues of right and wrong. Processes of reasoning can be taught, and school is an appropriate place to teach them. The reason is that, although parents and religious schools may teach ethics, they do not always teach ethical reasoning--or at least, they do not always do so with great success. They may see their job as teaching right and wrong, but not how to reason with ethical principles. How does one teach ethical reasoning? In the author's view, the way to teach ethical reasoning is through a case-study method, which is the principal method he now uses in his own course on leadership. An eight-step model of ethical reasoning is presented to illustrate how, within the context of a liberal education, ethical reasoning can be taught across the curriculum.