Two teens have been charged over a fire that caused about $2 million worth of damage to a high school in Hobart's northern suburbs on the weekend.
Classrooms, an assembly area, and a staffroom were destroyed in the blaze at Cosgrove High School in Glenorchy on Saturday night.
A 17-year-old girl and a 15-year-old boy were charged with arson.
Students were told to stay home on Monday as authorities investigated the fire, and are not expected back until Thursday this week.
Richard Stewart, who lives near the school, saw the fire in its early stages, and called emergency services.
"The school was unfortunately well alight, the pine tree had gone up, and the flames were probably a good 10 or 15 metres into the air," he said.
"There wasn't really much you could do but sort of watch."
The school will remain closed until Thursday partly due to safety concerns, as asbestos was exposed during the fire.
In a social media post on the night of the fire, Cosgrove High School principal Andrew Woodham called for resilience.
"This will be devastating news for our whole school community," he wrote.
"This will be a week where we all need to support each other and our core value of resilience will be on display."
Glenorchy Mayor Kristie Johnston said the whole community was behind the school.
"We give them our love and support," she wrote on Twitter.
Earlier on Saturday, fire crews were also alerted to a separate blaze at the old Claremont Primary School on Cadbury Road.
The Tasmania Fire Service said the building was a common target for arson.
Police are calling for any witnesses to either fire to contact Crime Stoppers.