Girls have dominated this year’s Higher School Certificate first-in-course awards, taking out more than twice the number of top spots compared with boys.

The strong result was powered by the exceptional performance of a systemic single-sex Catholic school in Sydney’s south, Bethany College. Five students at the Hurstville school placed first in the state across subjects ranging from design and technology to dance and studies of religion.

Roseville College student Stacy Zhang was the standout individual performer. She was named the best student in the state in both biology, one of the most popular HSC courses, and chemistry, after placing third in the state for mathematics advanced last year. Zhang’s classmate Sophie Firek topped legal studies.

At just 15 years of age, SCEGGS Darlinghurst student Anna (Chuyu) Luo placed first in the mathematics advanced course.

Anna, who has just completed year 9, was the only student at her school to take the course before entering year 12. She said she had an advantage over her older classmates, not having to juggle study for other HSC subjects.

When she is older, she would like to study pure mathematics at university.

“I think I’ve always liked maths, even when I was a child – it was always around me,” Anna said.

“When it gets challenging, I really like that feeling when you can solve a hard problem.”

Other girls with outstanding results included James Ruse Agricultural High School student Selina Ma, who placed equal-first in mathematics extension 1 and wants to study medicine next year.

Speaking on Wednesday, Selina said she spent year 12 inundated with study hacks from previous students at her high-achieving school that made her “feel so stressed and feel like a horrible student”.

“I think the most important thing is to find what works for you,” she said.

In the end, she found her own methods, and served as a maths mentor at her school to help other students in her grade and the year below.

“To be able to understand something to the level which you’re able to explain it is also one of the best strategies to learn,” she said.

In total, 139 first-in-course awards were handed out at a ceremony at the University of NSW on Wednesday.

Girls won 95 of the awards, while 44 were taken home by boys.

Private school students earned 56 per cent of the awards for coming first in a subject when language schools, where pupils undertake study separate from their normal schooling, were excluded.

Public school pupils made up 29 per cent of students who topped a subject, while Catholic school students took out 12 per cent.

Selective private high school Sydney Grammar continued its tradition of exceptionally high performance, taking out seven first-in-course awards, the most of any school.

Sydney Grammar students Alastair Herbert and Savya Mishra were equal-first in geography. Their classmate William Chung came first in both classical Greek continuers and extension, while Matthew Gu came first in both Latin and German continuers, and Jackson Chan topped French extension.

Other private schools with three or more first or equal-first awards included girls schools Abbotsleigh and Meriden, where Selina Wang came first in music 2 and music extension. Newington College also received three awards, including student Sebastian Wong for physics.

Public selective schools Baulkham Hills High and James Ruse also garnered three awards on Wednesday.

James Ruse student Terry Chen came first in one of the hardest courses of the HSC, mathematics extension 2, taking out the gong after scoring top marks in software design while in year 10.

When he got the phone call that he had topped the subject, he thought it was a scam.

“When I got the call, I was in a rush to go somewhere and I was just very shocked,” Terry said. “I thought it was a scam so I double-checked.”

Terry, who wants to study medicine at UNSW next year, studied with his friends by making a bank of questions they had got wrong throughout the year and revising them before exams.

Baulkham Hills High student Rahul Desai placed first in mathematics extension 1.

North Sydney Girls students Emily Phi and Valery Lin were named equal-first in English advanced.

In English extension 2, St Aloysius’ College student Yao Xiao placed first in the state with his major work exploring Shakespeare’s “leftover characters” – minor or marginal figures who he said resisted neat categorisation along ideological lines.

“I was interested in looking at why we value traditional texts, these classics, at the great classic of high school is Shakespeare,” he said.

It was one of many pieces Yao, who also studied mathematics extension 2 and wants to study law and mathematics at university, considered writing: at one point, he said, he was changing his hypothesis every two weeks.

“I felt sorry for my teacher, she was worried for a while because I hadn’t written much,” he said.

Presbyterian Ladies College student Jio Yim came first in English extension 1, capping off an impressive year for the student, who placed second in the world for her impromptu speech at the World Individual Debating and Public Speaking Championships in Kuala Lumpur in April.

Hornsby Girls graduate Alice Hynes, who topped history extension, has conflicting feelings about her results, and the HSC more broadly.

“To be honest, I kind of think that HSC itself, like on an institutional level, is just kind of dehumanising and ableist, I guess.”

Alice was born deaf and wears cochlear implants.

“It definitely has been a bit more difficult … I had disability provisions throughout the HSC.”

She wrote her major project on the role of climate historians in portraying environmental history.

“I was specifically interested in the role of historians and responding to the climate crisis,” she said.

with Cindy Yin, Emily Kaine and Siena Fagan