At Clancy Catholic College in Hoxton Park, students start preparing for HSC maths the day they start year 7.
Teachers focus on giving regular feedback, maths is applied to real-life scenarios and assessments are thorough and challenging from day one.
Their approach has paid off. The school has leapt ahead 18 places to make its first appearance in the top 20 of best performing maths schools.
The maths co-ordinator at Clancy College, Greg Georgiou, said the school took a "less traditional" approach to maths teaching.
"For me, the HSC starts the day they walk in year 7," Mr Georgiou said.
"It is important to us that it is about the type of thinking students do; not just about exam questions."
There is a drop-in maths centre before school for extra tuition for senior students, there are holiday classes and teachers hosted a pizza night before the trial HSC exams to be on hand to help students.
The school's top maths student, Matthew Arena, scored 100 per cent in the mathematics course, placing him 17th in the state. He received an Australian Tertiary Admissions Rank (ATAR) of 99.
Mr Georgiou said Matthew was not always a natural when it came to maths.
"When I look at his journey, he was a struggler but he came on board and was hungry for it," Mr Georgiou said.
Selective schools were again the top performers in high-level maths subjects, including Sydney Girls High which jumped 30 places to land in the number seven spot. North Sydney Boys and Baulkham Hills retained their second and third positions.
Knox Grammar was the highest non-selective school on the list, at number six. The top performing non-selective public schools were Killara, East Hills Boys and Lambton high schools.
Meriden School in Strathfield jumped 14 spots this year to ninth in the rankings, which includes mathematics and extension 1 and 2, while Malek Fahd Islamic School at Greenacre moved up 17 places to 18th in the rankings.
Top English schools
When it comes to the top performing schools in English subjects, selective schools featured less prominently on the list.
James Ruse was in the number one spot, but after that Freeman Catholic College at Bonnyrigg was the next top performer, followed by Moriah College at Queens Park and SCEGGS Darlinghurst.
Ascham, Sydney Girls and Baulkham Hills High were also on the list.
The only boys school to make the top 10 English list was the public non-selective school Balgowlah Boys.
The top public non-selective English performers after Balgowlah Boys were Galston, Menai and Willoughby Girls.