This curriculum unit explains that currently Asia has 9 of the world's 14 megacities (a city with a population of 10 million people or more) and that by the year 2015 there will be 27 megacities with 17 of them in Asia. The unit introduces students to several megacities in Asia and uses these cities as examples for understanding the ecological impacts a megacity has on its surrounding environment. The unit contains six lessons: (1) "Megacities and Air Pollution" (students examine what a megacity is, where megacities are located in the world, how graphs can be used to analyze trends, and the effects one region's air pollution has upon another geographic region); (2) "Energy and Society" (students explore the characteristics of energy use in the megacities of Beijing, Mumbai, and Manila; how energy use affects society and personal lifestyles, and the characteristics of high- and low-energy use societies; and guidelines for preparing brief overviews of the cities and presenting them to the class); (3) "Bangkok and the Scope of Water Pollution" (students discover various perspectives of Bangkok's water pollution problems and the ways the perspectives are interdependent, and the significance of water in Thai culture); (4) "Waste Management in Tokyo" (students learn the major ways people in Tokyo dispose of waste, the viability of these methods, and the similar methods that exist in students' home communities); (5) "Urbanization in Asia: Key Actors--Their Roles and Concerns" (students analyze the significance urbanization has on the environment of Asia, and the roles and concerns of key actors involved with environmental issues); and (6) "Sustainability of Megacities" (students examine the major environmental problems facing Asia, the major underlying causes of environmental degradation, and solutions to reducing environmental degradation). The appendices include sustainability game panels, sustainability game environmental IQ cards, color transparencies that show the energy use per capita for 1994, and the annual sulfur deposition for 1990. Handouts are included with each lesson. (BT)