The purpose of this study is to find out the jumping board utterances that lead learners to deep learning from the teacher's and students' utterances in science classes. We found that the quality of children's responses improved from the children's speech chains that often appear in Type B (Kanazawa, 2017), in which learners' peer responses emerge from the teacher's responses. It was found that the teacher's utterances, such as the way of asking, the content of the question, and the timing of the question, were the models for the formation of the interaction between the children and that the supportive utterances of the teacher-led to the interaction between the children. In this study, we analyzed the utterances in the classroom and found that the jumping board utterances of the students, which led to the deepening of the speech chain caused by the teacher's supportive utterances, deepened the children's understanding and recognition of their own affairs, although the teacher's supportive utterances could also be boiled by the jumping board. became.