The following paragraph is mis-leading...

The school was previously known as The Sydney High School, due to its position as the first government High School in New South Wales created under Premier Henry Parkes' system of public education in the early 1880s.

It can be interpreted as meaning Sydney High is the first government school in NSW.  Fort Street was the first government school in NSW (and Australia) est 1849.  
The paragraph should be re-written as follows....

The school was previously known as The Sydney High School, and was the first school created under Premier Henry Parkes' system of public education in the early 1880s.