Color changing ball

 My just-turned-six-years-old granddaughter was here and she brought some toys with her. When she first showed me this ball, it was as in this picture, mostly green with a little blue. However, she threw it up in the air and ....

 .... when she caught it, it was mostly blue with a little bit of green. It was like something out of a science fiction story. Whatever happened, happened so fast that you could not see it, like in a magic trick.

However, when I looked at it carefully, I could see that it was made of a lot of strange shaped curved pieces that moved when you threw it. In the picture you can see that my thumb is actually inside the ball. When I pushed on the surface some of the pieces turned over, changing the color. It was very clever.