All folded up and ready to magnify: The Foldscope weighs less than two nickels, is small enough to fit in your back pocket and offers more than 2,000-fold magnification. TED/YouTube hide caption

itoggle caption TED/YouTube

Vital Sounouvou is an African entrepreneur who founded Exportunity.com, a company to help promote trade in Africa. Courtesy of Vital Sounouvou hide caption

itoggle caption Courtesy of Vital Sounouvou

Women shout slogans during a protest against the gang rape and hanging of two teenage girls. Beyond highlighting the rampant sexual violence in India, the crimes are drawing attention to a glaring and fundamental problem across the country that threatens women's safety: the lack of toilets. Altaf Qadri/AP hide caption

itoggle caption Altaf Qadri/AP

The 85 musicians in the Santa Cecilia Orchestra are paid professionals who play with other symphonies and in Hollywood studios. Courtesy of the Santa Cecilia Orchestra hide caption

itoggle caption Courtesy of the Santa Cecilia Orchestra

The Liftware device, shown here as an early prototype (left) and the final design, starts up automatically when it's lifted from the table. There's no "on" switch to fumble with. Ina Jaffe/NPR hide caption

itoggle caption Ina Jaffe/NPR

Theoneste Rwayitare, a Rwandan refugee who resettled in Vermont last year, pours powdered milk into a bucket for milking at the Vermont Goat Collaborative's Pine Island Farm. Angela Evancie for NPR hide caption

itoggle caption Angela Evancie for NPR

Current water-filtering technology is costly, but MIT scientists are testing a simpler and cheaper method that uses wood from white pine trees. Wikimedia Commons hide caption

itoggle caption Wikimedia Commons

Melissa Conklin, 23, stands in the kitchen of her two-bedroom apartment at Woodmere Trace in Norfolk, Va. She earns about $30,000 a year at a nearby car dealership, and says these apartments are not only convenient, but affordable. She pays about $900 a month here, far less than other apartments in the area. Pam Fessler/NPR hide caption

itoggle caption Pam Fessler/NPR

Neonatal nurse Florence Mwenifumbo monitors a newborn receiving bubble CPAP treatment in Blantyre, Malawi. The device was developed by students at Rice University in Houston. Rice 360/Rice University hide caption

itoggle caption Rice 360/Rice University

Villages in the Lower Shire valley of Malawi, like this one named Jasi, rely heavily on subsistence farming and steady rainfall, and are struggling to produce steady harvests. Jennifer Ludden/NPR hide caption

itoggle caption Jennifer Ludden/NPR

Students at Ntimigom School in Kilgoris, Kenya, show off their e-readers. Worldreader now operates in 27 schools and two libraries in Kenya. Jon McCormack hide caption

itoggle caption Jon McCormack

Dee Faught tests a robotic arm installed on his wheelchair in September. Commercially produced robotic arms can cost tens of thousands of dollars, but three Rice engineering students built one for Dee for about $800. Eric Kayne for NPR hide caption

itoggle caption Eric Kayne for NPR

Christina Asima says she had no choice but to marry last year at age 12 to help care for younger siblings after her mother abandoned the family. But she says her husband was abusive, so she left him, and now must look after her 8-month-old son, Praise, alone. Jennifer Ludden/NPR hide caption

itoggle caption Jennifer Ludden/NPR

Young students in a Bridge International Academy school in Nairobi, in September. On the surface, there's little to distinguish these schools from others in the developing world. But Bridge's model relies on teachers reading lessons from tablets. Frederic Courbet for NPR hide caption

itoggle caption Frederic Courbet for NPR

Arunachalam Muruganantham installs his machine in a village in Chhattisgarh, India. Amit Virmani hide caption

itoggle caption Amit Virmani