The purpose of this study is to develop a program for environmental education that involves understanding conflicts about environmental planning and a fair distribution of their risks, using simulation and gaming. Like an election, there is a system that makes social determination collect an individual preference (Davis, 1973). It is said that it is required for citizens to participate in an argument for the purpose of adjustment of interest conflict by diversification of a sense of values. According to the viewpoint of deliberative democracy, the process of deliberation is important for an individual to be being able to think deeply (Renn et al., 1995). However, in an actual society, people only pay attention to one individual’s interest without paying attention to another’s. This makes it difficult to balance conflict in society. In this study, a participatory communication program for environmental education was developed using a game simulation. One of the advantages of playing the game is that it simulates situations that cannot be experienced in real life in a simple manner. By the player assuming the role of a stakeholder, and by reviewing their experience, it may be possible to understand the advantages and disadvantages of the environmental plan. An educational program on consensus building entitled “Stakeholders” has been developed (Sugiura, 2009). In this game, the stakeholders’ process of consensus building on the distribution of risks is experienced by players. To do this, the participants’ various sense of value is shown as a preference through visualizing each participant’s preference, and performing consensus building on the basis of this preference. When a social decision is made, the procedure and process of deliberation is examined, and the preferences are referred to mutually. The game simulation requires a group to determine an unanimous preference from alternatives concerning the 2R (reduce and reuse) behavior; the content of which is based on an actual stakeholder meeting on environmental planning in Nagoya, Japan. In the meeting the participants discussed the diffusion of 2R behavior and found some conflicts between stakeholders. In the simulation, on the other hand, players are informed of the role of the stakeholder’s preference at the beginning of the process. The group then chooses one alternative that refers to a preference. After that, each participant calculates the score by comparing the difference between the determined result and their preferences. The relationship between the result and the score distribution of an individual was discussed by the group. As a result, a relationship was found between the amount of variance of each score within the group and the degree of the group’s satisfaction with the result. Finally, the groups compared the score of each group among themselves and the relationship between fair distribution of risks and acceptance of a result was discussed. As a result, participants understood fair distribution of the risk in the case of interest adjustment, and people differ in terms of interest or risk. It considers a risk that people avoid. Participants notice a new criterion for decision making by referring to others’ preferences. The criterion of decision making in the actual life of a player may change. Finally, it is discussed that stakeholders can treat various subjects involving interest adjustment. It is possible to examine the analysis of deliberation and the system of evaluation, and what type of determination method leads to acceptance of a deliberation result. The process by which a preference and a sense of values change is also discussed.