D..
Please talk to the school. The next time she pulls this stuff, she could get a kid killed.
The reason she does this is so that she has something to DO. Not because she cares about the kids. A crossing guard is supposed to be watching the road and the children - not gabbing away with people.
I'd be plenty irritated over her attitude if I were you,too. But the real reason to talk to the school is because she is not safe for the children OR for the cars.