fifth, the synthesis step includes one strategy for sharing the peer assessment experience and providing instructor feedback.The aforementioned instructional support strategies for peer assessment were applied in the classroom, and the instructor’s and the learners’ responses were analyzed. The participants perceived that the classes were helpful for learning. In particular, the participants responded that the three steps of effective advice and the learner support tool were helpful for giving effective feedback in the peer assessment step, and that the iterative reflections and revisions improved the quality of the design. However, the participants reported the need to improve communication between the assessor and the assessee and to minimize the relationship effect. To address these needs, the strategies for peer assessment in STEAM design education were revised carefully.The results of the present study are meaningful in that they provide specific and practical strategies for peer assessment in the STEAM design education context and extend the research on peer assessment to elementary education context. By applying the instructional support strategies for peer assessment, the present study will contribute to the establishment of effective STEAM design education in elementary school.