At a recent graduation ceremony at Hanoi National University of Education, an American student stood out among the new graduates. David Coley, an alumnus of the University of Chicago, received his master’s degree in mathematics from the Vietnamese institution.

David William Coley (born 1986, United States) was among those awarded a Master’s degree in Probability Theory and Mathematical Statistics by Hanoi National University of Education on April 18.

A math teacher’s frustration with only reaching top students

David Coley has dreamed of becoming a mathematician since he was 16. After graduating from the University of Chicago, he worked as a math teacher. He admits that while he had strong theoretical knowledge, he lacked teaching experience.

“In my first year of teaching, I focused on delivering correct theory, but failed to help students connect the material to real-life applications,” David recalled.

“I assumed all students would understand my explanations. But I quickly realized that most were disengaged and confused. One even wrote poetry about how boring math class was. I was disheartened. Only a few students could follow the lessons - and they probably would have understood math even without me.

If only top students can grasp what’s being taught, what’s the role of the teacher? That realization pushed me to rethink my methods and find ways to make math more engaging for all learners.”

After teaching in the U.S. for some time, David moved to Vietnam in 2022 to work at a private school in Hanoi. There, he met two colleagues pursuing master’s degrees in mathematics outside of school hours.

“When I shared my dream of becoming a mathematician, they encouraged me to enroll in the same program,” David said.

He decided to pursue a master’s degree in Probability Theory and Mathematical Statistics at the Faculty of Mathematics and Informatics, Hanoi National University of Education, believing that applied mathematics would be more practical than number theory.

A math teacher dedicated to learning Vietnamese

David shared that he received tremendous support from his professors.

“Even though I often made pronunciation and grammar mistakes, the lecturers listened patiently and responded directly. Sometimes I only understood about 60% of their questions in class, but I still raised my hand to answer. Sometimes I was right, sometimes wrong - either due to math errors or language misunderstandings - but each attempt helped me improve,” he said.

He also appreciated how his classmates explained Vietnamese culture and education practices in a friendly, approachable way.

“Before exams, we would go to the library to study together. Afterward, we’d grab lunch. When it came time to defend my thesis, I was nervous about how to present it clearly in Vietnamese. Two of my closest friends came to my home to help me rehearse,” David recalled.

After months of effort, David received his master’s degree on April 18.

Associate Professor Dr. Ngo Hoang Long, who oversaw David’s major and taught him two subjects, praised David’s academic strength and strong sense of responsibility.

“Although we could have communicated in English, David always made an effort to speak Vietnamese. His learning approach and mindset were active and eager. When asked to explain a mathematical concept or result, he didn’t just recite definitions or properties - he also shared ideas about how it could be applied in real life. He was always willing to exchange insights with classmates and faculty, making class discussions more lively. It was a joy to teach a student like David,” said Dr. Long.

He added that David once competed in the prestigious Putnam Mathematical Competition, where he ranked 26th - a remarkable achievement in a contest involving top U.S. universities.

David believes that earning a master’s degree in Vietnam has provided a strong foundation for his future career. He is currently pursuing a PhD in mathematics in South Africa and hopes to apply the knowledge gained in Hanoi to solve real-world problems there.

Thanh Hung