The Bangor Daily News reports police arrested the 15 and 16-year-old boys late Friday night.
The bomb threat, found in a second-floor bathroom last Tuesday, forced officials to evacuate the building.
A fire in the same place closed school the following day.
No one was hurt in either incident.
The boys are expected to be charged with arson and making a bomb threat – both felonies.
They’re scheduled to appear in court Thursday.