POLICE are calling on the public's help to identify the person or persons who started a fire at Laidley State High during the school holidays.
The blaze, which detectives believe was deliberately lit, took hold at 4.30am on Easter Sunday.
The fire damaged two art classrooms and two business classrooms were smoke affected.
Laidley police Sergeant Jim McDonald described the crime as "disgraceful" and asked anyone with information to phone Policelink 131 444 or call Crime Stoppers on 1800 333 000.
DETECTIVES and firefighters are on the trail of arsonists following what has been dubbed a "disgraceful attack" on a Lockyer Valley school.
Fire tore through two classrooms at Laidley State High School at about 4.30am on Sunday, following what police now believe to have been a break-in and deliberate lighting of a blaze.
Laidley police Sergeant Jim McDonald said forensic examinations were being carried out, while local detectives have been door-knocking nearby homes.
"This is a disgraceful attack on one of our community's facilities and we are focused on catching those responsible," Sgt McDonald said.
"Extensive door knocks have been occurring. Any further information at this stage is critical."
Initial investigations carried out by the Gatton Criminal Investigation Branch indicate offenders gained entry to two blocks at the school, also attempting to gain entry to a third block, before gaining entry to a fourth block and lighting a fire.
Gatton CIB Detective Senior Constable Scott Petrie said two classrooms were extensively damaged and equipment destroyed.
"Scientific police have examined the scene," he said.
"We believe an accelerant was used.
"The four surrounding streets to the high school have been door-knocked.
"We remind everyone to call Crime Stoppers and if they have any information to assist.
"Investigators from the CIB and CPIU are investigating, being a high school."
Police said a quick response from firefighters helped reduce further damage.
The school told parents via Facebook that it was planning to relocate art and business classes which were directly affected by the fire.