Almost $39 million will be spent expanding the school, with the project set to be completed by the end of the 2018 school year.
Education Minister Peter Collier last week released a more detailed timeline of the project, which was announced in December, after the State Budget was handed down.
He said the 2018 works, which would be completed in two stages, were necessary for the school to accommodate increased student numbers.
�The school is experiencing a trend of growth in student enrolments,� Mr Collier said.
The number of full-time students rose by 23 from 2012 to 2013, but from 2013 to 2014 it increased by 85 to a total of 1566.
With the addition of Year 7 students this year, the school saw more than 700 new students.
Stage 1 of the works, which will include double storey science and art blocks, sports hall and 18 classrooms on the southern end of the school grounds, are expected to be completed by January, 2018.
Stage 2 is set to be completed by September the same year and will see the gymnasium demolished to make way for a technologies block which will include woodwork, metalwork, jewellery and machine room.
The major expansion will come after $10.7 million was spent last year for a Year 7 building, which has nine classrooms, two science labs, visual and performing arts studios, and an IT laboratory.