Sand Dollar

Oh jeez, that last picture didn't load the last time I was here, yes it's a sand dollar. Most likely Clypeaster rosaceus, also known as the sea biscuit! Fits both the location and appearance (that very wide, almost flower like star in the middle).

Sand dollar, a relative of the urchin

Yep, this is a kind of sea urchin called a heart urchin, they belong to a group of Echinoderms called Spatangoida. Hard to ID, so maybe try and find an ID book for this specific area! But neat find :D

Yes, this looks like sea urchin.