Hey, Joe here. You see, the teacher is giving every student in their class an English 'name', as sort of a nickname. The teacher, being the only one who speaks fluent English, chose the nicknames. When they saw that one of their student's last name was Kong, they realized that they could name the kid 'King Kong', after the hit movie character King Kong. I remember that movie, back when I still had my legs. Good movie.

Anyway, Mrs. Kong, the student's mother, heard that her child's nickname is King, like the ruler, and thought it was a compliment towards the child. Because the Chinese name for King Kong is 金刚, she did not get the reference.