Aidan (age 7) and I know that sharks must keep swimming to breathe and stay alive, but do they actually sleep or just rest? Do they have eyelids?

Sharks don't sleep, they have active and inactive periods.

Anatomy of a Shark

http://www.everwonder.com/david/sharks/anatomy/

(Scroll down to sight)

First of all, not all sharks need to swim to breath. There are several that will lay quietly on the sea floor or motionless under a rock ledge.

Secondly, sharks do have eyelids.

Lastly, science has yet to determine whether or not sharks sleep. At this point it is an unknown.

Aidan says that he knows the angel shark can stay on the bottom of the ocean and not move ... it looks like the sand.

Are their eyelids clear? It is hard to see where they might be in pictures when the shark's eyes are open.

Note, the eyelid is opaque and not all sharks have them.