SimIsle: Missions in the Rainforest is a simulation game released in 1995 by Maxis and developed by the legendary Will Wright.
SimIsle was one of the lesser-known Sim titles, and certainly one of the less popular ones. However, the premise of the game was still rather unique, and as usual, very educational without seeming "academic".
The game puts you in control of a group of people: environmentalists, scientists and the like, who advise you on how to proceed. Each mission, you are given control of an island or islands, with a set of objectives to reach (drawing a certain population, etc.) How you go about completing the objectives is up to the player, but the game focuses greatly on showing consequences of actions - hence the very strong environmental theme of the game.