He remained inside as the fire spread until the smoke forced him to flee via the back door.
Once outside he stood and watched as the mobile classroom went up in flames before phoning the fire service and telling them the location of the blaze.
Fitzpatrick hid in the netball courts and watched the fire crews putting out the fire.
The mobile classroom and its contents were destroyed resulting in about $250,000-$260,000 in damages which Fitzpatrick is not in a position to pay.
The Life Education Trust is a charitable trust which uses the mobile classroom to teach about 14,000 Western Bay pupils from primary school age upwards about making informed life choices.
Fitzpatrick's lawyer Craig Horsley told Judge Christopher Harding that the arson was not only a a tragedy for the community but for his client whose background circumstances made "tragic" reading, but that was not an excuse for his offending.
Mr Horsley urged the judge to take into account that Fitzpatrick had expressed remorse for his offending and was willing to participate in a restorative justice meeting with the trust.
Judge Harding said the pre-sentence report did indeed make tragic reading, and referred to Fitzpatrick as being a "socially mal-adjusted young man" with an inadequate and severely dysfunctional background .
He noted that Fitzpatrick had not attended a mainstream school since 2005, and he had an extensive offending history, and the longest he had held down a job was for eight days.
The judge said it seems that Fitzpatrick held some form of resentment towards education authorities and his actions had caused very significant loss to the community.
However, Judge Harding said given Fitzpatrick's age and very unfortunate background he was prepared to grant him leave to apply to substitute the sentence with home detention, if a suitable address became available.
Since the blaze, the Life Education Trust has received a huge amount of community support.
School children and businesses in the Bay have donated $8000 towards resourcing a new Life Education Trust mobile classroom.