He began teaching at the Yonhee Technical School (the predecessor of Yonsei University) in 1926, but in 1938 was removed from the service due to his involvement in a 1938 incident at the Heungeop Club [ko].
[1] He was reinstated as a librarian at Yonhee College in May 1941, but resigned in October of the same year due to the Joseon Language Institute incident.
After the surrender of Japan ended World War II, Choe became the head of South Korea's Ministry of Education's Textbook Compilation Bureau[2] and served two terms, once from 1945 to 1948, and then from 1951 to 1954.
At the time of its publication, Korean Language was the most advanced grammar book in terms of the breadth and accuracy of cited data and clarity of logic.
While Choe is mainly remembered for his contribution to scholarly research of the Korean language, he also displayed interest in developing a pedagogical approach to Hangul, beginning with his 1925 graduate thesis on the pedagogy of Johann Heinrich Pestalozzi.
In The Way of Rehabilitation of the Korean People (조선민족갱생의 도, 1926), Choe synthesizes pedagogy with nationalist enlightenment ideals and diagnoses "defects in the nature of the Korean people"[5] In this text he investigates what he believes to be the historical causes of these defects and proposes a revival of cultural and ethical principles including patriotism and loyalty as the solution.
[6] Despite this, it is undoubtedly due to Choe that the modern Korean textbook still utilizes the horizontal writing system, of which he was a strong proponent of.
As a scholar, he was a vanguard in standardizing and establishing the study of Hangul grammar as well as pedagogical and theoretical approaches to the Korean language movement.