The cooperative relationships among team members are not recorded. This study adopted the idea flow analysis method proposed by Alex “Sandy” Pentland and proposes a mode, denoted as industrial design team idea mode (IDTIM), for analyzing the ideas developed by industrial design teams. Students from a design department at a university were recruited as the research subjects, and these subjects applied two types of discussion mode to execute the experiments. The experiments entailed using a reality mining approach to observe the students’ discussions according to five categories of interaction patterns. The IDTIM was applied for executing analytical tasks. The results are as outlined follows: (1) A team with high cooperation performance developed design works with relatively high quality; (2) interactively evaluating the idea flow and the draft of design concepts generated through team cooperation effectively assisted instructors in instructing student design projects; (3) executing the IDTIM enabled the students to actively express their opinions; (4) visualizing the idea flow information facilitated clearly understanding the perspective of student team cooperation; and (5) using the IDTIM technique assisted instructors in effectively instructing team design projects.