The National Atlas of Korea is an online atlas that can also be downloaded as a pdf. It has a variety to topic maps and even has some lesson plans for teachers to use with the atlas.
This is a valuable site with information that is otherwise difficult to find on the country level for Geography Teachers. Teachers can use these maps for a variety of geographic activities - looking for patterns using two different maps, teaching the students how to ask geographic questions (in which maps are needed for the answer), a deeper dive into Korea and many of the topics provided.
The Atlas is housed in three editions and the teacher would need to direct the student to the correct one. There is even a children's edition that could be used for upper elementary students. The Atlas is also available in FOUR languages - Korean, English, French and Spanish.
http://nationalatlas.ngii.go.kr/us/index.php
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