In the past, say, 50 years how many children have died from a shotgun shell absent a firearm? Zero? You believe they are dangerous because?
You can kill someone with a pencil by stabbing them. I would worry more about kids with pencils then kids with shotgun shells. I bet the statistics would confirm this if anyone cared enough to look it up.
I don't know. How do you know?
You believe they are dangerous because?
They contain gunpowder and a primer cap. Seems pretty obvious to me. Of course they can be handled safely, and even casually. But in the hands of someone immature and intent on mischief they can be dangerous. And if you can't see the difference between a pencil and live ammo, I'm afraid I can't help you.