Soil and Soil Science Education in the Primary School Through Appearance of "흙[heuk], Soil" in the Korean Reading Textbook

Public education on soil and soil science in Korea was reviewed through textbooks written in Korean which were used in the primary schools since 1950's. Numbers of words 흙[heuk], the Korean native word meaning soil, and 토양[土壤, toyang], originated from Chinese characters, were counted, and compared with the textbooks published in 1950's, 1970's, and 1990's, 2010's. The Korean native word "heuk" was used 20 times in 1950's, and increased to 55 times in 1970's. In 1990's version, it was decreased to 31 times and to 20 times in the 2010's version. The first appearance in the 1950's version was in the 3rd grade book, but was in the $1^{st}$ grade books in both 1990's and 2010's. In this recent version, the primary school students met this word on the poet, "Toad, Toad build a house", and "Sprout come out through soil clod". The word, "토양, toyang", originated from Chinese characters, 土壤, appears only 2 times in the $6^{th}$ grade in 2010's version. Authors conclusively recommend children should learn meaning of soil at early stage of primary school easily with positive image.