This series raises a very realistic issue of children's education in Korean society.
Minju, who lives in江北 (Gangbuk), has been raising her son all by herself through hardships. Fortunately, her son Jinu is an ambitious child who has always been the top student in his school without attending any cram schools, and Minju takes pride in this. However, in an English competition, Jinu's score was lower than that of Seo Mi's daughter, a classmate of Minju's whose rank is 20th in her school in the江南 (Gangnam) district. Minju realizes the severity of the issue.