The Component Model of Reading expanded upon the Simple View of Reading by adding an ecological and psychological component. Elements of the ecological component include teacher knowledge, information provided in textbooks, and teacher instructional practices. In this study, the authors examined the extent of teacher knowledge about text structure, the extent to which textbooks focused on text structure related skills and strategies as well as the percentage each skill and strategy was covered in lessons and teacher instructional practices. Such analysis shows that although text structure interventions may have positive effects on student reading comprehension, there are multiple elements of the ecological component that may be counteracting the benefits of the intervention. First, teachers have a limited knowledge of the five common text structures. Second, textbooks systematically minimize text structure instruction and only cover comprehension skills and strategies sporadically throughout a year-long curriculum. Third, teacher learning of text structures and change in practice was moderated by these ecological factors including textbook scheduled instruction and administrator support.