The National Incident Management System (NIMS) identifies concepts and principles that answer how to manage emergencies from preparedness to recovery regardless of their cause, size, location, or complexity.
NIMS for schools is no different.
Here in Colorado, this is what is required of schools:
If you do not know what is "required" in your specific location, we certainly encourage you to find out. If there are no requirements, or you find the requirements "lacking", you may want to consider using the above graphic as a "model" of sorts.