In Europe, leaders tried to cobble together another bailout loan for Greece.
The Dow Jones industrial average was down 99 points at 12,910 shortly before noon Monday.
The Standard & Poor's 500 was down 10 points to 1,399. The Nasdaq composite index also fell 10 points, to 2,957.
Macy's, Target and other retailers fell as investors worried that the strong start to the holiday shopping season may not last.
A White House report warned that if lawmakers and President Barack Obama don't reach a budget agreement that consumer spending would suffer.
McGraw-Hill rose after the company said it would sell its textbook publishing business to a private equity firm.