The corneas in a person's eyes are the only bodily cells that do not receive a blood supply.

I can't answer for all, but young kids, hopefully, learn many new facts on a regular basis. I learn from my grand kids each time I visit with them. Personally, I try to learn something new each day. It is difficult to not do so, being surrounded by news media and the internet. Just this morning they showed a new species of insect and named it after Lady Gaga because of its strange appearance. (I don't see it.)