ABSTRACT
When people offer a model of a system at smaller than full scale, they accomplish two things: First, they enable visitors to visualize things they could not otherwise see, to get an overview of the system that would not be possible at full size. And second, they engage visitors. School buildings designed to use natural daylighting or passive solar heating illustrate in an immediate way the changing angles of the sun. How we build, what we plant, what food we eat, how we travel, how we consume resources, how we handle rainfall, whether we let streams flow or send them into storm drains, all these convey ideas and illustrate our policies about the world. A waste audit is a graphic and effective way to make often-abstract waste and recycling concepts visible. "Green infrastructure" replaces the concrete pipes and channels with rain gardens and vegetated swales to cleanse the water with plants and microorganisms and then let it infiltrate the soil.
