The author demonstrates a new system useful for class reflection inspired from "lesson study," a process in which teachers jointly plan, observe, analyze, and refine actual classroom lessons called "research lessons". Our new system offers an environment that one can use an iPad to bookmark observers' feedbacks into simultaneously recorded videos in the environment. If one uses video recording and feedback check sheets in class reflection, one can easily use the system, and makes learning more effective and efficient because of the following two main reasons. 1. Participants instantly reflect on his/her performance by watching scenes supplemented with both aggregate and synchronized individual observer's feedback. 2. Observers can give detailed feedback to the performer based on visual evidences and bookmarked feedback information, which make their learning more clear. [For the complete proceedings, see ED579282.]