I spent a few years in Singapore in the 90s aged 5-8. We were taught to cross the road with a hand in the air. I think this is still the case for children in SG today. It wouldn't help so much in a driveway situation but at pedestrian crossings it can be the difference between getting home safely or not.

Kids should be taught to be aware of their surroundings and that if you can't see the driver of a vehicle, then they likely cannot see you either.

Ultimately though, all that is really just a last-resort safeguard against driver inattention and/or poor parenting. The driver of the vehicle should be 100% responsible for their actions, regardless of safety assistance features like cameras.

Even in my own experience of rear view cameras, pedestrians crossing close to the rear of the vehicle are obscured by the rear pillar until the last second, so it doesn't make mirror checks optional. I imagine similar issues exist for forward-facing cameras where a child walking towards then across the front of the vehicle could be obscured by the A-pillar until it's too late to stop. Again, the driver is responsible to check those areas by moving their head or even getting out of the vehicle and physically checking the blind spot if there are any doubts.