标题:614 中学生における時代観念の発達 (日本教育心理学会第4回総会部門別研究発表要旨・討論の概要 : 15. 教科の心理・教授過程) [in Japanese] 614. Development of concept of "era" among junior high school pupils. (TITLE OF PAPERS AND THE SUMMARIES OF DISCUSSIONS : 15. Psychology of subject matters : Teaching prosess) [in Japanese]