The Palm Beach County School District has had at least 14 threats so far this school year.
All of these threats are still under active investigations but still no arrests in any of them.
Tuesday, two threats sent into two different Palm Beach County schools, one by email and one by phone.
The district says majority of the threats are made either by phone or email, the threats are hard to trace.
The district says the phone call threats are not real numbers and not real voices.
NewsChannel 5's Internet Security expert Alan Crowetz, ofinfostream.cc says there are many apps and sites that allow you to hide your number and your voice.
He says you can fake your account info, too .
"A lot of these apps are mom and pop shops that set up over night and then disappear."
Crowetz says police have to trace the app or site used to make the anonymous call and hope they cooperate.
"We could subphoena them and do they still have the log? And it was it the hotel computer they called from or a fake phone," said Crowetz. "So each hop requires an enormous amount of time and effort."
It is just as difficult to track the email threats. Crowetz says these criminals are using obscure email servers, possibly overseas, also with fake account information.
"It is very difficult. Not only is it technologically challenging to go through all of these hops and barriers but it take a lot of time."
Then it is the same story. Police would need to track down the email sever and hope they cooperate.
Crowetz says a a lot of these apps and sites are notorious for being uncooperative with law enforcement which is why they end up having to take legal action to get data.
Technology is not the only way the district's received threats, some have come from writing on the walls.