A new exhibition opening September 30 at the Cooper Hewitt Smithsonian Design Museum aims to highlight design projects that use art, architecture, urban planning and design to address issues of poverty and sustainability. The show, called “By the People: Designing a Better America,” is the third in a series the museum has curated about socially responsible design. Curator Cynthia Smith spent two years conducting field work to find the designs that will be included in the…