[HBKXNCUO]

That may have reduced the likelihood, but closing them down would not prevent incidents from showing up in this list. For instance, check https://www.schoolsecurity.org/trends/violent-deaths-and-sch...

>March 16, 2005: Covington, KY

>A man was shot to death and two people were wounded in an altercation about 40 yards from an elementary school. The school went into a lockdown. The incident did not involve individuals associated with the school, but a teacher at the school had heard the shots and the school was locked down to protect students and staff.

The shooting only needs to take place near the school to make it on the list, and by the way this was the only gun-related injury in March on that list.