Haley Nordeen, 19, is spending the entire summer at the Prodesenh center in San Mateo Milpas Altas, Guatemala. The American University student helped build the center's new library.
Usman (right), 7 months, and Abdullah (left), 18 months, are held by their mothers while they wait to receive the polio vaccine at the Jalozai refugee camp near Peshawar, Pakistan.
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A health worker gives a child the polio vaccine in Bannu, Pakistan, June 25. More than a quarter-million children in Taliban-controlled areas are likely to miss their immunizations.
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Gary Kendrick, 8, works on his freestyle stroke with help from a counselor at Ransom Everglades School. Kendrick did not know how to swim before he started lessons at the school.