Carrie Underwood learns the old ways on Tony Bennett's Duets II.
Politicians use Taylor Swift's D.C. concert to raise money.
Merle Haggard shows his "Fightin' Side" is still very much intact.
Martina McBride and Darius Rucker help send kids back to school.
The Civil Wars move their battle lines across the U.S.
Caitlin Rose does her mom proud on NPR's World Café.