Tom at Thinking It Through points out this story, which notes that among the dead in Fallujah are "three boys under 11 years old."

The Guardian has this explanation of the demonstration:

A local Sunni Muslim cleric, Kamal Shaker Mahmoud, told Reuters that the demonstrators had gone to a school occupied by US troops to ask them to leave.

"They were asking the Americans to leave the school so they could use it," he said.