Classes have resumed after two classrooms and the school's internet hub were destroyed by fire at Holy Family Primary School on Sunday.
The school's multi-purpose hall will be a temporary classroom for 51 year one pupils and two teachers for the next two weeks while they wait for two new demountables to arrive.
Pupils returned to school on Tuesday after the school was closed on Monday.
Principal Sister Brenda Kennedy has been overwhelmed by the community's support since Sunday night, when a building at the school was completely destroyed.
It consisted of two year one classroom, a storeroom and the school's main internet and phone hub.
Police were unable to enter the scene until Monday.
It's believed an electrical fault caused the fire, which isn't being treated as suspicious.
What's left of the building will be demolished this week.
''The community has been very supportive,'' Sister Kennedy's secretary Denise Carroll told the Star.
''There were parents here soon after the fire started, keeping an eye on it. We've been inundated with offers of help, flowers and messages of support from other schools, both Catholic and public, including Emerton Public School.''
Firefighters from six stations were called out to the Emert Parade school just 5pm on Sunday after numerous triple-0 calls.
It took firefighters 90 minutes to extinguish the blaze.
Around 50 people attending a religious function in the school auditorium at the time of the fire evacuated.
Parents turned to the St Marys-Mt Druitt Star Facebook page to express their shock.
‘‘My daughter is so upset -all their hard work through the year gone up in smoke,’’ Todd Hackett wrote.
More in the October 27 edition of the St Marys-Mt Druitt Star.
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