The arrest, at an otherwise unreleased address, came in conjunction with a search warrant jointly served by local police and members of the FBI's Joint Terrorism Task Force.
Computers and other electronic items were seized during the raid, but no explosives or firearms were found, Schauerhamer said Friday.
Authorities did not release the suspect's name, given his juvenile status. However, Schauerhamer said state and federal prosecutors would review whether to seek trial of the teen as an adult.
Detectives and FBI cybercrime experts obtained evidence of threats against the school, as well as police officers and their families, from Skype and Facebook accounts allegedly accessed by the boy.
The motive? "A general disdain for law enforcement," Schauerhamer said.
Skype and Facebook also provided information that helped investigators eventually trace the boy's calls though they had been deliberately masked by rerouting through numerous sites and other unspecified means.
"He [used] fairly sophisticated techniques to cover up his tracks," Schauerhamer said, noting it took "hundreds of man hours" to eventually run down the suspect's IP (Internet Protocol) address to a Saratoga Springs location.
The boy was booked on suspicion of making threats of violence via the 911 system and terroristic threats with weapons of mass destruction, among other offenses. He was incarcerated Friday at a juvenile detention facility in Utah County.
More charges could be forthcoming: Police and FBI investigators also are checking into other incidents across the country where the youth may have made threatening or bogus calls to various 911 dispatch offices.
On Tuesday, Alpine School District officials canceled classes at Westlake High after receiving threats, via audio-only Skype calls, to explode multiple bombs on campus unless a $10 million cash ransom was paid.
While some 2,200 students got an unexpected extension to their summer vacation, the Utah County sheriff's explosives squad, aided by bomb-sniffing dogs, swept the school room by room. No bombs were found and Westlake was cleared for classes to begin Wednesday.
Schauerhamer confirmed the suspect had once attended Westlake High, but recently had been involved in "distance learning" and taking classes online from home. He did not know whether the home-schooling was the result of disciplinary action by the school.
Police also declined to discuss if there were any specific grievances the youth may have had against the school in general or students and teachers specifically.
Police did confirm they had made "numerous" visits to the teen's home during the past year on other matters, but they would not detail the nature of those calls other than to say they were "unrelated" to the bomb threats or similar violent allegations.
Schauerhamer specifically said he knew of no "criminal history" the boy had with police.
Alpine School District and Westlake High administrators did not immediately respond to requests for information on whether the suspect had been expelled or left the school due to other disciplinary reasons.
However, Westlake High's website did carry a statement Friday morning reading in part:
"As an Administration, faculty and staff, we would like to thank Saratoga Springs Police Department and the FBI for their quick and immediate action to ensure the safety of our students."