2.  There are many  mountains in the world.

3.  Some mountains have fire inside:

4.  VOLCANOES!!! And they do this: http://www.youtube.com/watch?v=R0Zbj7S22zs

5.  Because some things get excited and explode when they get too hot.

6.  To find out why think about solids, liquids, and gases. These are solids. You can touch them when they are cool.

7.  If you heat ice, it becomes water: (and if you heat water it becomes a gas): If you heat metal a lot, it can also become a liquid…

8. When rock is hot it can become lava:

9.  And when the lava gets really hot it makes lots of gas called CO2. This gas gets excited and wants to escape, so it explodes out of the volcano.

10. Look here for more information: http://www.youtube.com/watch?v=2M5JQDdardM