http://www.koreasociety.org/
The Korea Society is an organization that is dedicated to promoting better awareness and understanding of Korea. It is based in New York and holds many different outreach programs, including language classes and film screenings. They also hold museum exhibitions, but the website doesn't provide any sort of online access to the material.
Most relevant to us would be their educational resources section, which has a huge database of curriculum materials developed by teachers, many of whom took study tours to Korea. The lessons cover various topics for many different grade levels. It is very easy to navigate. Here is the direct link:
http://www.koreasociety.org/korean-studies/new_educational_resources_page.html
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