The are souvenirs from the China Pavilion at Expo 2012 in Yeosu, South Korea but I do not know what they are.
Each disk is about 2 1/4" in diameter. The fronts are convex with printed images; a mascot and the symbol of the China Pavillion. The back is flat and plain.
Google Translate can't seem to decide on how to translate the Korean characters.
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