The purpose of this study was to examine art-teachers' role and their particular prerquisite for teaching broaden and diversified knowledge in art as well as ever-changing art concept with its various art materials and mediums in order to understand the present and the prospect of in-service art-teacher education in Korea for the year 2000. This study included the literature review on the transition of art concept, the diversity of art materials and mediums and a pertinent direction for its changes which art teachers could present to now generation preparing for the new era. In order for students 10 understand the essential concepts in art, followings should be considered as a core curriculum to implement in accordance with its structural and systematic teaching plan and study progress . 1) To understand and equip the skill the use or art materials and mediums: 2) to understand the symbolic meaning of visual form in artwork: and 3) to distinguish the similarity and difference between the characteristics and form in various artwork. In conclusion, what art teachers should face with and challenge for teaching broaden and diversified knowledge in art with its extended concepts and materials are follows ; 1) To understand and implicate various visual form which can be identified as art in order La comprehend distinctiveness of art concepts; 2) to acquire the knowledge of high technology, media and skills which could possibly produce art image; 3) to be flexible in one's thinking for accept the knowledge on various art forms and arc production progress; 4) to arm with art theory to identify what meanings and values can be deter mined as an artwork; and the last, 5) 10 have the knowledge and information or, art philosophy, educational methods, school administration and its organization.