Multiple bomb threats evacuate schools this school year

 Between 15-20 school bomb threats were made in Ohio.   
I understand why school administrators don't want to exaggerate the bomb threats that have been called in to numerous schools--often elementary schools--over the last few weeks.
  On October 20, 2015, these schools and more received bomb threats, including 2 this month in Perrysburg:

• Covedale Elementary and Wilson Elementary in Hamilton County,
• Fairfield East Elementary and Middletown High School in Butler County,
• Donovan Elementary School in Warren County and
• Summit View Elementary in Kenton County.
• Lakota
• Perrysburg Woodland
• Perrysburg Frank School
• Lakota Endeavor Elementary
• Oakdale Elementary School
• Edgewood Elementary School
• Denver Place Elementary
• Summerside Elementary 
• West Clermont Schools said that "eight other schools across Cincinnati"

Other states:

• Union County, Ind. schools
• Riverside Elementary School in Princeton in New Jersey
• Cresskill  New Jersey
• Robert Wood Johnson Hospital in New Jersey
• West Milford Middle School in New Jersey
• Cherokee Elementary School, Arizona
• Scottsdale Unified School District , Arizona
• Parkview Elementary School, Arizona

  The same problem occurred on October 7 and September 25 according to Homeland Security, who "monitored" the bomb threats in previous situations, including the September 25 bomb threats.
  To deal with this, it appears that many administrators are choosing not to evacuate the schools because it gives "power" to the perpetrator of the threatener.
  In San Diego, in what the district termed "unprecedented", 11 high schools were threatened on September 17 in "the most threats ....ever handled on a single day."
  Some have proven to be the traditional culprits--high school students anticipating tests, trying to score a day off or even a grudge.
  Rashes of threats are nothing new but a concern that some of the calls have been automated has been raised, as this article relates in Tennessee, five of which were made on August 31:

The threats were made with an automated voice over an internet service. Similar threats have been received in other areas of the state. Multiple agencies are working to find out if they are connected. Individuals found responsible could face felony charges.

  Several day care agencies were targeted in Ohio this week also. 
  The FBI is also looking into the bomb threats, which would certainly tell observers how well prepared each school was in defending itself.
  We don't forget Beslan.  
UPDATE: And today, Connecticut.

An unprecedented rash of threats phoned in to San Diego high schools Thursday kept more than 21,000 students in locked-down classrooms as police systematically swept 11 campuses but found no suspicious devices or people. - See more at: http://www.sandiegouniontribune.com/news/2015/sep/17/high-school-bomb-shooting-threats-lockdown/#sthash.xaVlemJE.dpuf