An annotation tool for lesson study

†Development of Computer and Information Sciences, Tokyo University of Agriculture and Technology †††Information Media Center, Tokyo University of Agriculture and Technology 2-24-16, Naka-cho, Koganei-shi, Tokyo,184-8588 Japan ††Center for Higher Educational Development, Tokyo University of Agriculture and Technology 3-5-8, Saiwai-cho, Fuchu-shi, Tokyo, 183-8509 Japan E-mail: 50007258508@st.tuat.ac.jp, {t-terada, Kathy, egichan, w-tsuka, nakagawa}@cc.tuat.ac.jp