번호판을 읽던 아이The Boy Who Read Number Plates

Everyone named in these essays has given permission.

I went there to teach

At an academy in Britain, I met a student preparing to apply for mathematics at Cambridge. I had not come to Britain to prepare for university. Towards the end of my military service, I had applied for a working holiday. Once there, I did various jobs, including the familiar work of teaching maths. Watching that student, I thought: I could do this too.

When I give a short account of my background, I tend to begin with Cambridge. But I had not planned my life around getting there. First I took students’ questions at an academy. Then I did my military service and went to Britain. The idea of going back to university came along the way.

Before all that, I was a student who had always been good at maths. Having a subject you do well in can make life easier: at least it need not be another worry when exams approach. Familiarity, though, does not excuse a lack of preparation. I learnt that quite early, in a middle-school statistics exam.

Getting my best subject wrong

I was born on 9 February 1991 in Daejeon. We lived in Dunsan-dong, then moved to Wolpyeong-dong, and I went to Seongryong Primary School. My parents say that, from a very young age, I was interested in the numbers on car number plates whenever we went for a drive. This is something they have told me, rather than something I remember for myself.

In my fourth year of primary school, I was selected to represent Daejeon in a maths competition and won a prize. In October of the second term of fifth year, we moved to Seoul and I transferred to Eunjeong Primary School. There, too, I joined the gifted maths class and placed highly in national competitions. I went on to Mogil Middle School and Daeil High School, an ordinary high school in Seoul.

So I cannot claim that I was a child who struggled with maths. I liked it and did well at it. I do not think I need to change my childhood to explain why I now tell students to write their working down. It is also true that I made mistakes when I worked things out only in my head, and that those mistakes led me to develop the habit of writing.

In middle school, I did badly in a statistics exam. I had found the topic uninteresting, neglected it and sat the exam without properly learning the concepts. Being good at maths did not prepare that particular topic for me. Afterwards, I stopped treating recognition as enough: I practised until I could actually use a concept in a problem.

Nor did the importance of method come to me in one sudden revelation. As a student, I helped friends; later, I taught students. Exploring mathematics freely and solving a set of problems within a time limit called for different preparation. My thinking developed over years of seeing that difference.

From learning to teaching

At the academy I attended in high school, there was a teacher called Mr Choi Kyung-jae. He had studied mathematics education at Seoul National University and had taught maths for many years. Above all, he was exceptionally capable at the subject and drew a great deal out of me. I never had private tutoring or took online lectures, so that academy was a strong influence during my school years.

Later, he asked me to tutor his son. The person who had taught me was entrusting his own child to me. That was different from being praised as a student. I now had to explain the maths I knew so that another student could understand it. Mr Choi now runs a Naver online community called Areunyuga.

My parents supported me completely. Perhaps that was because I was doing well. Had they pushed me to do better, I would have rebelled. I was that kind of child. I am grateful that they trusted and encouraged me, though I do wish they had set clearer rules for everyday life. Perhaps they held back because I was so rebellious.

So when I tell parents to trust their child, I do not mean that they should set no boundaries. Understanding and encouraging a child can go alongside expecting them to observe everyday rules. That is the distinction I want to make when I talk about my own parents.

Becoming a student again

I entered university in 2009. That May, I began a part-time job in an academy’s study hall, taking students’ questions. It was my first work as an instructor. Military service followed. Before my discharge, I saw a notice for the first intake of YMS, the UK’s Youth Mobility Scheme working-holiday programme. I wanted to see a wider world, so I applied and was accepted.

I did various jobs in Britain, including teaching maths at an academy. When I met the student preparing for Cambridge, I was already someone who taught, but I could become a student again myself. Standing on the teaching side did not mean that my own education had to be over.

I thought mathematics suited me better than engineering. I sat STEP, the examination taken by applicants to mathematics at Cambridge, and received S, Outstanding, across the board. I think that counted for a great deal in my admission. I entered Trinity College to read mathematics on a scholarship covering full tuition and living costs.

If asked what frightened me as a teenager, I cannot think of much. It was an age that did not know fear, and some of that remains in me. Yet if I could speak to that younger self, I do not think I would tell him to get better marks. “You are going to have a great many experiences later on. Don’t let studying be all you do.”

A child who liked maths had entered a mathematics course, but that did not mean I enjoyed every part of it. At Cambridge, there were subjects that did not suit me and times when I disliked maths. Even for someone accustomed to doing well in exams, there was unfamiliar work ahead.