Sky Jumpers by Peggy Eddleman

Hope lives in a post apocalyptic town in the American Midwest.  Green bombs have destroyed the cities, and most of the people and technology, but have left no lingering radiation.  They have also left a gas called "the Bomb's Breath" that is poisonous and more dense than regular air.  All the adults are afraid to go near the pockets of Bomb's Breath but the kids have figured out that if they hold their breath, they can jump through it and fall so slowly it is like flying. This understanding of the Bomb's Breath comes in handy when bandits invade the city and try to steal their most valuable commodity, antibiotics. 

I thought this was an interesting take on a post WWIII world.  The war had taken place just 40 years earlier, so the older people in town remembered having technology and a highly populated world, but the kids had only heard stories.  I had to raise my eyebrows a bit when the story asserted that the green bombs had altered the characteristics of metal world wide, so that it had lost its strength and they had to make everything out of wood or stone.  Not sure how that worked.  Still, the story wasn't really about surviving after the bomb, it was about a little girl who uses her courage and strength to save her family and town.  It was a fun read and an interesting setting and I look forward to reading the second in the series (which I just realized came out in September but I haven't ordered for the library yet.  Oops.  I will get it ordered today.)  275 p.