We've noted in previous reports on teacher prep that when we evaluate hundreds of courses that prepare elementary and special ed teacher candidates to teach reading in the early grades, we need to review hundreds of their required reading textbooks. Some courses use textbooks we've reviewed previously, but far fewer than one would expect.
Reading textbooks though, as we have found in our work, are in seemingly endless supply. Quality discussions aside, the sheer quantity relative to other fields suggests a serious lack of consensus.