The $9 million Bloomberg Philanthropies contest also awards innovations from Chicago, Houston, Philadelphia and Santa Monica.
The eighth in our series exploring the class divides across America's largest cities and metros.
Five winners will be announced this spring, but these ideas stand out above the rest.
Would you dissolve in fire or would your clothes simply ignite?
A look at which major U.S. cities have the most fatal car crashes per capita.
The percentage of accidents involving alcohol varies widely by city.
It's been an eventful year for cartography.
From residences to gardens to installations, a look at the most compelling works of the year.
Homicide rates have fallen significantly in some places. Does economic development deserve the credit?
Metros with strong job growth, low vacancy rates and low foreclosure inventory.
So far there are only three of them in the U.S. The rest of us are still working on it.
The United States is not just as a single national economy but a collection of city and metro economies, and they're growing at starkly different rates.
As Massachusetts governor, Romney was a believer in smart growth, climate change and mass transit. But the same man may not enter the White House, if he wins.
Texas master-planned community The Woodlands still isn't interested in becoming a city, and they have a strong case.
Project Row Houses transforms Depression-era homes into a community art museum and affordable housing.
One in seven young Americans are neither working nor going to school.
Jakarta bests New York and L.A. as well as Tokyo, London, and São Paulo, according to a recent study.
Don't be fooled - sprawl is about much more than the number of homes per acre.
Increasing income inequality is changing the patterns of where Americans live, according to a new report.