Threats at work or school cause real panic -- hoax or not. As a result, perpetrators can face real legal consequences.
Criminal charges or not, any student playing such a prank will end up with a permanently tarnished academic record. And youngsters aren’t exempt: kids under 18 can still be tried as an adult in most states, depending on the seriousness of the crime and the judge’s discretion. Youngsters playing pranks could face juvenile detention or other penalties. Parents should make children aware of the ramifications of such pranks or actual threats.
Cited from: The Legal Ramifications of a Bomb Threat http://nakedlaw.avvo.com/safety-2/the-legal-ramifications-of-a-bomb-threat.html#ixzz2qHnEQVe3