The Jetsons didn't foretell the future; the Flintstones did. At least, that seems to be the lesson implicit in San Francisco's first 100 percent "off-grid" building, a self-contained ecology classroom at Heron's Head Park. The facility won't use city sewage or electricity services, but instead relies on wetland cells and ultraviolet sterilization lamps for wastewater treatment, and solar panels and a wind turbine for electricity. The center boasts a living roof, and is surrounded by low-maintenance native plants. Run by the nonprofit Literacy for Environmental Justice, the EcoCenter teaches schoolchildren the ins and outs of clean air and water, healthful food, and open space restoration. It will also explain how dirty industries and facilities sometimes get put in poor neighborhoods. Interns will be trained as resident naturalists and docents.