Religion classes, in any form that they may appear in a public school, do not teach religion as fact (or they shouldn't). The class should be structured as a study of the religion, it's beliefs and origins, how it relates to other religions and their origins, and it's impact on society/history. The validity of the beliefs shouldn't ever come into play. Because of this, there is no need to "teach the controversy," because there is no controversy where no truth claim has been made. Frankly, a properly structured religion curriculum, might instill more doubt in people than any science class ever would.