To find professional web sites on Google, try this approach:
active shooter site:gov
or
active shooter site: edu
This way you narrow your search down. to government or educational sources. You could use "org", "mil", "com" etc. also.
Length: 900 – 1,000 words
Documentation Style MLA
Sources Journals: at least one
Newspapers and magazines: at least one
Government or police documents: at least one
Professional web sites: at least one
Books: at least one
To find information in the JSCC Library's book collection (both print and electronic), try using the following words:
active shooters
Columbine
school violence
school shootings
Serial killers