The project team is developing a prototype of Eco, a multi-player game to prepare high school students to be environmentally literate citizens with 21st century skills. To play the game, students will enter a shared online world featuring a simulated ecosystem of plants and animals. Students will co-create the civilization by measuring, modeling, and analyzing the underlying ecosystem. Students advocate proposed plans to classmates and make decisions as a group. Cooperation and science-based decision making activities are necessary for success in preventing the destruction of their environment. The prototype will include teacher resources to support the alignment of game play to learning goals, and implementation. In the Phase I pilot research, the project team will examine whether the game prototypes function as planned, if teachers are able to integrate it within the classroom environment, and whether students are engaged with the prototype.