Thaumatropes

A thaumatrope is not that hard to make. You take 2 pictures on paper (one is a background and the other is an object) and glue them or tape them onto a piece of thin poster board. (The pictures are on separate pieces.) Tape the pictures to a pencil and tape the edges together.

When you roll the pencil back and forth in your hands, you can make it look as if the fish is on the background. Why? When you roll it in your hands the pictures are going too fast for your brain to process the two pictures separately so it combines the pictures. That is my science experiment.