Response is pretty much a no brainer. It boils down to a reaction - a reaction from first responders all the way up the chain from individuals, schools, communities, counties, and state and federal governments. It can be something as simplistic as a house fire to something as gigantic as a hurricane. It can affect a few, or it can affect many. What is done in reaction to these events, both emergencies and disasters, is "Response".
On the FEMA site, Response and Recovery are together on one page. For schools, there really isn't anything we could find definitively focused on Response or Recovery specifically. A search found multiple links to a number of sources of information.
In most plans, Response is included in the planning process. Again, model plans are out there, some better than others. Do your research, and choose what works best for you, your organizations, your school, and your community.
U.S. Department of Education:
U.S. Department of Education also wraps their information on response into their document, Practical Information on Crisis Planning. It begins on Page 4-1.
Don't forget, while these documents and resources are directed primarily at schools, themselves, that does NOT mean community members cannot also use them in helping schools in their own communities put together viable, realistic emergency management/crisis response plans.