Columbia subject headings:
School violence--United States--Prevention--Handbooks, manuals, etc.
Schools--United States--Safety measures--Handbooks, manuals, etc.
Threats--United States--Prevention--Handbooks, manuals, etc.
Harvard subject headings:
School crisis management--United States.
School violence--United States--Prevention
Princeton subject headings:
School violence--United States--Prevention--Handbooks, manuals, etc.
Schools--United States--Safety measures--Handbooks, manuals, etc.
Threats--United States--Prevention--Handbooks, manuals, etc.