sand dollars

I just learned a lot about sand dollars. They are a sea urchin. They can be found in any ocean that is not cold. When it is alive they are brown and furry. When they die they become hollow and float up to the surface of the ocean and float ashore. They loose their fur when they die and become light brown. When we where in Pensacola Florida we where on a hotel on the beach. When we went out to swim we would find a lot of parts of sand dollars. We only found two full round ones.