The graph in slide 11 is the radial part of a wave function, we need to square this to get the probability density function. Then it would be a graph starting from 0,04 after which it’d make a hill.
I would describe this to a child as some sort of diffuse spherical shell, with a darker zone at the atomic radius and very bright at infinity. The child would not be standing in total brightness, but there would be some dark in his spot.