From the Document: "Schools are an important part of the infrastructure of communities and play a critical role in supporting the whole child, not just their academic achievement. This guidance is intended to aid school administrators as they consider how to protect the health, safety, and wellbeing of students, teachers, other school staff, their families, and communities and prepare for educating students this fall. This guidance is for K-12 [kindergarten to 12th grade] school administrators who are preparing for students, teachers, and staff to return to school in fall 2020. School administrators are individuals who oversee the daily operations of K-12 schools, and may include school district superintendents, school principals, and assistant principals."
Centers for Disease Control and Prevention: https://www.cdc.gov/