Utilization of IoT and AI is a big chance not only for large enterprises but also for small-and-medium-sized enterprises (SMEs) and local communities. However, it is not easy for them to realize it. We have proposed "innovation design method." This method consists of frameworks such as value design (value proposition canvas), system design (SCAI graph), and strategic design (customer value chain analysis, open&closed canvas). In this paper, the innovation design method was applied to ideathon for solving regional challenges of Nomi City. Here, it is necessary to renovate the local communities and resources. We integrated the framework of "community renovation" into the existing innovation design method. In the "Nomi City × AI / IoT ideathon", 16 students participated in 4 days intensive group work based on the innovation design method, then proposed four
solutions utilizing IoT and AI. The effectiveness of the proposed innovation design method includes:(1) to efficiently diverge and converge ideas with short-term concentrated group work, (2) to recognize and claim the intrinsic value of the proposed solution, and (3) to visualize what kind of value should be provided to whom using the community renovation framework.