다시 수험생이 되던 날The Day I Sat the Exam Again

The other people in this essay have been left unidentifiable.

Jajangmyeon and tangsuyuk

I found out that I had received a first-round offer for dentistry at Yonsei University through its essay-based entrance exam while eating alone at a Chinese restaurant. I was having jajangmyeon and tangsuyuk: black-bean noodles and sweet-and-sour pork. After checking the result, I finished my meal. I told my family, who said it was good news. That is about as much as I remember of the moment.

I did not make an announcement to my students either. Some saw it on my website and said it was impressive. I had told no one while preparing. Had I failed, it would quietly have come to nothing. I was not particularly frightened.

Put like that, even the reason for taking the exam can sound slight. But there was something I wanted to find out. Could I, the person telling students about a method, actually use it in Korea’s maths exams? So I worked through past papers and sat the exam on my own.

An instructor in the exam hall

There was no special occasion behind my return to Korea. I had graduated, so I came back and began teaching various kinds of university-entrance maths in several places. The work I had done before Cambridge had become my full-time occupation.

People who hear my background sometimes ask why I teach grade-10 and grade-11 students rather than the very strongest final-year students or medical-school essay-exam classes. I wanted to see, from grade 10 onwards, where the difficulties faced by grade-12 students began. In the study book’s prologue, I compared it to small cracks eventually bringing down a dam. I wanted to meet students when those cracks were first appearing.

Yonsei’s essay-based entrance exam for 2022 entry took place on Saturday, 2 October 2021, before the CSAT. Nothing remarkable happened that morning. I took my writing materials and admission slip and arrived on time. A thirty-year-old instructor sat among final-year school students.

There were four maths problems. The first used rolls of a die to construct an isosceles right triangle and asked for the expected perimeter and number of interior lattice points. The last involved polygons formed by drawing line segments inside a triangle. It asked for a vector-sum argument showing that equal numbers of polygons met each of the triangle’s three sides.

It called for sustained written solutions, the kind of work I had struggled with in my first Cambridge supervision. This time, as I wrote, I thought: I’m going to get in. The candidate beside me had an almost blank answer sheet. As I wrote in the study book’s prologue, more than a hundred candidates were competing for each place, but my recollection of my own thoughts is surprisingly brief.

After the exam, I probably went back to work. I do not remember what followed as a grand occasion. I did not put everything aside to wait for the result; I found out over a meal. The exam was something I had fitted into my life.

Being able to solve it

After the essay exam came the CSAT. I chose Calculus in the CSAT for 2022 entry and scored a raw 100. In Probability and Statistics, I scored 100 in the September KICE mock exam for 2023 entry; in Geometry, I did the same in the September mock for 2024 entry. Those are full raw marks in three subjects, earned in different exams.

Sitting among school-age candidates, I naturally noticed the age difference. What caught my attention more was how difficult students found it to move past a problem they could not solve. Time was passing, yet they stayed where they were stuck. They were missing the moment to move on to another problem they could answer.

In a classroom, a teacher can pause a solution and speak to a student. In the exam hall, candidates have to choose their next action for themselves. I saw that difference from a candidate’s seat. Later, I could draw on the experience when explaining exam management in class.

The three score reports record that I could solve those exams. My marks do not become my students’ marks, though. Explaining my method, helping a student use it on their own problem and finding out where they have stopped are further tasks. Passing an exam had not completed that work.

Life after admission

I did enrol in dentistry. But teaching was my work, and I kept taking leave from university. The academic demands made it hard to do both. One reason I sat the pharmacy essay exam for 2024 entry was to move to a course with a relatively lighter study burden. I again received a first-round offer, but did not enrol in pharmacy: I could not remain enrolled in both places.

A short biography can put the two offers side by side: dentistry, pharmacy. Actually attending university while continuing to teach was less simple than those two lines suggest. Being able to gain admission and being able to sustain the life that followed were different questions. I was continuing to teach.

In the study book, I describe maths as a “decoding skill” that can be developed through training. I can contribute my own exam experience to that argument. I cannot erase the fact that I had been good at maths since childhood and say that everyone need only do what I did. There was more work to do in finding out where students struggled.

Once, after teaching at my own pace, I was told that my lessons were too fast even for the highest class in a medical-track academy. Completing my own answer in an exam and waiting for a student’s working in class were different tasks.