When I saw this PIN I knew it was something I had to try. After all, you only need an empty bottle, a clear plastic bag and some string. I cut the bag in half, used some dental floss to tie a head, and cut the bottom into strips. Then I filled the bottle water with water adding a few drops of blue food color. Fill the head with water and tie off the dental floss. Squeeze the plastic bag creature into the water bottle and secure the cap. The "jellyfish" will float up and down when the bottle is turned. Really fun to watch and sort of creepy too. My kids thought it was real! Super Cool!