Students participate in a team-building activity. These 13- and 14-year-olds are vulnerable to gangs and have already been exposed to violence. Fifteen students who attend Chicago Public Schools have died by gunfire this school year. David Gilkey/NPR hide caption

Last fall, Oregon Rep. Peter DeFazio was the subject of a political ad paid for by the Concerned Taxpayers of America — which turned out to be a million-dollar front group financed by just two men. Read more about that ad, and how DeFazio followed the money. Jonathan Ernst/Getty Images hide caption

Hundreds protest in Islamabad, waving the flags of the Jaamat Islami Party and Pakistan Tehreek-e-Insaf, the party of former cricket player Imran Khan, now a politician popular among young Pakistanis. Sajid Mehmood/NPR hide caption

Spent nuclear fuel rods are stored in pools of water at Japan's Fukushima Dai-ichi nuclear power plant. The water keeps the rods cool while protecting the environment from their radiation. Jiji Press/AFP/Getty Images hide caption

Frog Design and ECOtality created the Blink family of recharging stations for the Chevy Volt, Nissan Leaf and other electric vehicles. frogdesign.com hide caption