If you're criticising vulnerable road users (ie. kids) because you think they might be hurt by dangerous ones (ie cars) for being in the Wrong Place, you're victim-blaming. It's exactly the same principle as telling women that they ought not to go out at night in short skirts in case men attack them. Exactly.
In the Netherlands, there was a campaign in the 1970s called Stop de Kindermoord (Stop the Child-Killing) and it took off, and led to the development of safe routes to school (and elsewhere). In the UK, we focused on Stop, Look and Listen, and drummed the message home into generations of kids that if they get run over, it's their fault - not the fault of the people behind the wheel. The result? Numbers of kids walking or cycling to school plummeted. Children aren't allowed to play outside their homes, or walk down to the park unsupervised. We've started imprisoning our children because we can't curtail the car, instilling habits of indolence and dependence upon motorised transport. And air pollution contributes to 40,000 early deaths per year.
OP, I really do appreciate your genuine concern for the kids in the scenario you describe, but if a car runs into a mum getting a child out of a stationary car, the fault is with the driver of the moving one. Nobody else. You shouldn't be driving in a residential area - and particularly not outside a school - if you aren't absolutely sure that, if a kid were to run out into the road, you couldn't stop in time.
@cakedup - I really appreciate your focus on walking and cycling, and I'm really glad that London boroughs (and others) have started to take safe routes to school seriously. However, that line "of course they shouldn't.." still implies victim-blaming.
Nobody has the right to kill or injure another person. We've just allowed ourselves to be socialised into thinking it's ok, as long as you're in a car.