Once they hit elementary school (and often before then), they are sent to private schools after school to study more. Once they are in high school, many go to private schools and study until the wee hours of the morning. One math/etc hagwon that I used to live near had classes until 1 AM. The students then had to be up and back at school before 7:30 or 8 in the morning. They get homework from regular school as well as homework from the hagwons.
High School is often said to be the hardest as the competition to get into a good university is very tight. They base everything on which university they get into, with Seoul University being the best in the country.
Korea Near Bottom of the Class for Education
May 16, 2008
Korea ranked high among world countries in higher education achievement but near the bottom in quality.
In the IMD World Competitiveness Yearbook 2008, published by the International Institute of Management Development in Switzerland, Korea is ranked a poor 53rd among 55 nations in terms of university education meeting the needs of a competitive economy, one of the indices that indicate quality levels.
In contrast, the country ranked fourth in the percentage of population that has attained at least tertiary education for people aged 25-34. That brought Korea's overall ranking in education competitiveness to 35th among the countries surveyed, down six notches from 29th in 2007. The country's ranking in education competitiveness has been yoyo-ing from 44th among 60 in 2004 to 40th in 2005, to 42nd among 61 in 2006 and 29th of 55 in 2007.
Competitiveness rankings were given according to compatibility with a competitive society, qualified engineers available in the labor market, and knowledge transfer between companies and universities.
Korea ranked a high fifth in scientific infrastructure, up two notches from last year, and top in patent productivity, a gauge of patents granted to residents or research and development personnel in business, fourth in business expenditure on R&D, and fifth in total expenditure on R&D out of GDP.
The country came 14th in technological infrastructure, down eight notches from 2007, due in large part to lack of sufficient technological regulations and cyber security. Korea ranked the lowest among 55 nations in the IMD survey on whether technological regulation supports business development and innovation.