When Berkeley graduate Eric Ryan was sent by Teach for America to a hardscrabble high school in the heart of North Carolina's NASCAR country, he didn't count on Harold Miller -- a big guy with a big laugh and a tarheel accent as thick as sorghum syrup -- sticking his head into his class one morning and announcing, "Hey Mr. Ryan, we're gonna build an electric car." Two regional utilities had challenged a group of elite schools throughout the South...