Revealed: The secrets behind Sydney’s top schools for HSC maths

Five years ago, the principal at Concord High decided to upend the school’s year 7 timetable to ease the often rocky transition for students making the leap from primary to high school.

“We introduced a middle school model to focus on that transition,” explains Victor Newby. “We now group subjects like maths and science with one teacher, and English and history with another. It means year 7 students have six teachers rather than 12, which helps make that move into high school smoother.”

It was among multiple changes at the inner west high school in 2020, including employing a senior study coach for HSC students, and starting an after-hours algebra club for year 10s.

Concord High is one of several schools to achieve improved average HSC scores in mathematics over the past three years, a Herald analysis of public school final exam results has revealed.

Concord’s average HSC score across all maths courses taken has jumped more than three marks to 83.4, placing it in the top five non-selective state schools.

Academically selective school North Sydney Boys High achieved the highest average score in maths, with an average across all maths courses of 91.7.

James Ruse scored an average of 91.4, while Baulkham Hills scored an average mark of 90, narrowly eclipsing Sydney Boys High (89.9) and Normanhurst Boys (89.5). Most fully selective schools offer only advanced maths and extension 1 and 2 subjects, rather than the standard courses.

The analysis, from data published in 385 NSW public schools’ annual reports in 2024, reveals those achieving strong maths results across their entire student cohort, not just band 6 results.

Kathy Kalachian, head of maths at Concord High, said teachers had a laser-like focus on consolidating core maths concepts in years 7, 8 and 9. “By the time they get to year 10, if there are too many gaps, it’s very difficult to catch up.”

She credits the weekly algebra club for helping year 10 students who want to take advanced maths build greater fluency in calculus, which they need to excel at higher levels.

“In years 8 and 9 we try and expose all students to the same maths content, including advanced content, because for some students, they don’t start to pick up their act until the end of year 9.”

Newby said establishing a senior learning centre for HSC students and hiring a teacher to act as an “academic coach” had contributed to the lift in results. “We’ve changed the mindset from having free periods that lacked focus and purpose to making the most of that time to prepare for HSC tasks and assessments.”

Improving students’ sense of belonging from year 7 through the middle school model has helped set up students for success in years 8 to 10, he says.

The analysis showed powerhouse non-selective school Balgowlah Boys achieved the highest average HSC score among the state’s comprehensive schools for all maths courses, at 88.4.

Another single-sex school, Epping Boys, achieved an average of 84.9, and Killara High scored 84.5.

Balgowlah Boys has long appeared at the top of the end-of-year HSC league tables, and under the leadership of former principal Paul Sheather the all-boys school tripled enrolments and became famed for its success in HSC English.

Chris Hickford, head of maths at Balgowlah, said quality explicit teaching, high expectations from the start of year 7 and setting students challenging tasks had helped students succeed in year 12 maths.

“We have a focus on student accountability, providing work and assessments that challenge them, and never letting them become overly comfortable,” said Hickford.

“When new staff start at Balgowlah they go on observational teaching rounds. Going into classes and watching other teachers helps get them up to speed as fast as possible. It shows them what good teaching looks like, including in maths, which [is] grounded in explicit teaching.”

Sheather has previously pointed to the school’s improvement in reading and literacy as having a direct influence on maths scores, as these skills are needed to understand the questions. “We have done a lot of work on literacy and writing.”

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