The Korea Herald : The Nation's No.1 English Newspaper

The Korea Herald : The Nation's No.1 English Newspaper: "The educational districts of Gangnam (Gangnam-gu and Seocho-gu) in Seoul and Imshil in North Jeolla Province showed the highest academic achievements, while Goksung in South Jeolla Province marked the lowest.
None of the sixth graders in Imshil scored below the basic standards in English. The Education Ministry attributed Imshil's high performance to the three-day English immersion camps sponsored by the county and after-school classes run until 6 p.m. in each school.
Goksung had 8.5 percent of its sixth graders below the basic standard and 50 percent in the 'proficient' level.
In Gangnam, 95.1 percent and 93.6 percent of the sixth graders scored 'proficient' in English and math, respectively."

Korea Herald does a little bit more with the standardization testing stats. Perhaps they are from Gangnam and Korea Times is from Goksung.