Page 1 - VOLCANOES
P. 1

SAI INTERNATIONAL SCHOOL

                                                        CLASS-3

                                                  LN – Volcanoes

               Learning Objective - Students can describe common features of volcanoes. They
               can draw a diagram to represent a real volcano.


               How do volcanoes occur?
               Sometimes a big crack develops in the Earth’s crust.
               Magma from the mantle travels up the crack and shoots
               out or erupts on the surface of the Earth. This is called a
               volcano.
                     Once the magma erupts on to the surface, the
                       magma is called lava. The lava has flowed, cooled
                       and hardened into rocks.

                     The layers of lava form a flat surface called a volcanic plateau. Besides lava,
                       some volcanoes send out rocks, volcanic ash and gases.
                       ash and lava. The ash is burnt lava.
                     The most common type of volcano is a composite volcano. It has layers of



                     Some of the magma forces its way through cracks in the sides of the
                       volcano. When this magma erupts it forms baby volcanoes called secondary
                       cones.



               Important parts of volcanoes:


               Crater – large hole at the top of a volcano where material
               erupts


               Vent – a hole

               Magma – Melted rocks

               Secondary cones – small volcano that erupts on the side of
               the main volcano.


               Learning Outcome – Students learnt about the common features of volcanoes.
               They can draw a diagram to represent a real volcano.

               Let’s do an activity: Children will draw the model of the volcano and label it in

               their copy.
   1