So you already know that some volcanoes can be destructive,  but did you know they can also be helpful?  

Some volcanoes can change the land very slowly. Sometimes lava flows out of a huge crack in the earth's surface or on the ocean floor.  These types of volcanoes can change the land in many ways.

As a matter of fact, much of the earth's surface began with volcanic eruptions.  Examples are on the sea floor itself, some mountains and islands.