Here's a game you can play that will show you something about how matter changes state. You don't need any supplies except a lot of kids.
How does dry ice perform this disappearing act? Why is dry ice dry?
Frost-free freeze physics--it's more than a tongue-twister.
Most birds you see standing on only one leg are doing an impressive balancing act while tucking the second leg into their feathers. This is much easier to recognize in large birds, such as flamingos, but the behavior itself is common to most birds.