The report is organized to provide information on the school-level implementation of alternate assessments for students with significant cognitive disabilities. Following the Introduction in Chapter 1, Chapter 2 describes the study design and methods, including the development of the teacher survey and data collection procedures and analyses. Chapter 3 describes background information for teacher respondents, the students they teach, and the classrooms in which they work. Chapter 4 describes teachers' potential instructional influences, their understanding of the alternate assessment system, and their expectations and beliefs related to students with significant cognitive disabilities. Chapter 5 describes the teachers' professional capacity and the availability and use of resources. Chapter 6 describes students' opportunity to learn academic content. Chapter 7 highlights key study findings. National Study on Alternate Assessments Teacher Survey is appended. (Contains 1 table, 60 figures, and 10 footnotes.)