K-12 SCHOOl-ASSOCIATED CLUSTER: An educational institution that has been found by their local health department to have multiple cases comprising at least 10% of students, teachers, or staff, within a specified core group OR at least three (3) cases within a specified core group meeting criteria for a probable or confirmed school-associated COVID-19 case with symptom onset or positive test result within 14 days of each other, AND no likely known epidemiologic link to a case outside of the school setting. COVID-19 cases who may have shared exposure on school grounds and are from different households are included. Case counts for school-related outbreaks include those associated with before and after school programs (e.g., school-sponsored sports, etc.). K-12 SCHOOL-ASSOCIATED OUTBREAK: An educational institution that has been found by their local health department to have multiple cases comprising at least 10% of students, teachers, or staff, within a specified core group OR at least three (3) cases within a specified core group meeting criteria for a probable or confirmed school-associated COVID-19 case with symptom onset or positive test result within 14 days of each other; who were not identified as close contacts of each other in another setting (i.e. household) outside of the school setting; AND epidemiologically linked in the school setting or a school-sanctioned extracurricular activity. COVID-19 cases who may have shared exposure on school grounds and are from different households are included. Case counts for school-related outbreaks include those associated with before and after school programs (e.g., school-sponsored sports, etc.).