MATHS tutor Ong Ai Ling first took the O-level examinations nearly 20 years ago, when she was 16.
Back then, the former River Valley High School student received A1s for elementary and additional mathematics.
Yet for the last two years, she has taken both O-level maths papers as a private candidate.
The 34-year-old was not looking to improve her already stellar grades, but felt it appropriate to experience being a student sitting the exams.
"Teaching is one thing, but taking the exams is another," said Ms Ong, who has been authoring 10-year series books for both subjects for the past five years.
"I wanted to put myself in the shoes of my students. Then I will be in a better position to advise them."
She still scored A1s in both subjects on both tries.
However, it was not an easy task, said Ms Ong, who has a chemical engineering degree from the National University of Singapore.
For her latest attempts, she went through two months of intensive revision prior to the exams, mainly working on past-year papers.
"When I first studied for the exams years ago, my teachers emphasised a lot on the 10-year series questions. But in the last few years, the questions were more challenging," she said.
"The syllabus for each subject keeps changing. These days, the 10-year series book provides a basic foundation. Relying on it alone is not enough to score."
To help students who have not been doing well, Ms Ong, who co-founded maths and chemistry tuition centre Winners Education Centre, adopts unconventional methods of teaching her subjects, rather than simply asking her students to memorise formulae.
For example, she likens variables in maths equations to different kinds of people and uses stories involving these "people" to show how a change in one variable can affect another.
One of her students, Ng Kai, 17, a former St Joseph's Institution student who sat the O levels last year, said: "It was assuring to have our tutor prepare for the exams along with us. She would know first-hand the difficulties we face in the examination halls."
This article was first published on Feb 25, 2015.
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