OpenGames: A Framework for implementing 3D Collaborative Educational Games in OpenSim Ioannis Champsas, Ioannis Leftheris, Thrasyvoulos Tsiatsos, Theodouli Terzidou, Apostolos Mavridis Aristotle University of Thessaloniki, Department of Informatics, Thessaloniki, Greece ichampsa@csd.auth.gr ilefther@csd.auth.gr tsiatsos@csd.auth.gr lterz@csd.auth.gr apmavrid@csd.auth.gr Abstract: The main goal of this paper is the presentation of the design and implementation of a game framework, for building 3D collaborative educational games. The final framework, which is called OpenGames, supports the creation of such games, in the virtual worlds of the open source platform, OpenSim. This paper presents the steps followed for the implementation of this framework, its technical aspects, as well as the first impressions and evaluation results after the conducting of a game based educational activity. Keywords: 3D Virtual Game Based Learning, Virtual Learning Environments, OpenSim, Game Framework, Serious Games 1. Introduction Game Based Learning (GBL) is a rapidly evolving process in which educational computer games are integrated into the traditional educational approach. This kind of games motivate and help students to acquire new knowledge and skills in a way that traditional teaching would not be feasible or could be difficult to achieve. In these games, educational and entertainment aspects co-exist and can help in achieving better learning outcomes. According to Prensky (2001), the basic features such games have are the following:  Rules: Establishing some rules is essential for the smooth conduct of the game, as well as supporting the players.  Objectives: Players should try to achieve a specific goal.  Result and Feedback: The game should provide an additional incentive beyond learning, to motivate more the students. Furthermore, there should be appropriate feedback to each correct or incorrect action of a player during the game.  Concurrency: the existence of competition between players or those and the computer can achieve better learning outcomes.  Interaction: it should be clear that the decisions the players make, will be those who will judge the final result, e.g. between two groups answering questions, the winner should be the one, whose members studied more.  Plot: In some cases the existence of a plot in the game can draw more attention from the students. The goal of this work was to develop an easy to use and configurable game framework that can be used to create 3D collaborative educational games with such characteristics. OpenSim was the platform of our choice for developing this framework, after a research that took place at the beginning. The final implementation can be used to create hidden questions type games in which students participate in teams and try to discover and answer correctly multiple choice questions hidden in a virtual world. During the implementation, attention was paid into making the potential games as customizable as possible, so that are able to adapt to different learning objects or situations. After the implementation was over, and in collaboration with another thesis titled "Design and Evaluation of Cooperative Educational 3D Game," a snapshot of a game was created in a virtual world of OpenSim. The result was the conduct of an educational activity in which undergraduate students of the Department of Informatics of our University participated. In this activity an educational game was created, with questions based on the undergraduate course "Web Learning Environments". It was the first time the framework was tested in real conditions and the first impressions were very promising. The few problems we encountered were insignificant and they were not technical related but mostly procedural. In order to investigate the effectiveness of the final framework, this paper addresses the following research questions (RQ):