There are three main types of volcanoes that exist on earth, shield volcanoes, calderas volcanoes and composite volcanoes. The shield volcano is different from the others because it does not have a traditional pointed top. Instead, shield volcanoes are low and rounded which resembles a shield lying on the ground. Making volcano models is a popular school project that can be accomplished using inexpensive supplies. Volcano models should be an accurate representation of the exterior of the volcano as well as simulate a volcanic eruption of lava.
Spread a layer of newspaper over a table or other flat work surface to protect it.
Place a baking tray onto the surface to support the base of the volcano. Locate a piece of cardboard to use as the base of the volcano. Cutting the side off of a cardboard box using scissors will work well. The cardboard can be any size that you like, but should be cut into a square shape using scissors.
Cut the top off of a 473ml. plastic soda bottle using a utility knife. Make the cut at a slight diagonal angle. Turn the bottle upside down and apply 1 tsp of glue to the bottom of the bottle. Place the bottle, glue side down, onto the centre of the cardboard and press down. Allow the glue to dry for one hour before continuing with construction.
Begin forming the volcano around the bottle using modelling clay. Spread a wide layer of clay along the base of the cardboard and build up around the bottle to create a gentle domed shape. Remember that shield volcanoes do not have sharp peaks like other volcanoes. Continue adding more clay until the desired shape is achieved. Do not place clay inside the bottle.
Use the sharp tip of a pencil, or other pointed object, to create small channels that run from the top opening of the volcano down to the outer edges. Insert the tip of the pencil until it is approximately 1/8 inch deep and drag it along the surface of the clay. This creates lava channels through which the lava will flow when the volcano erupts.
Allow the modelling clay to dry for one to two hours.
Spray paint the clay to achieved the desired colouring of the volcano. Shield volcanoes are not very tall, so there should be no white snow caps on top. Shield volcanoes are various shades of brown and tan, and green paint can be added to represent trees. Allow the paint to dry for one hour before proceeding.
Pour 1/2 cup of vinegar, three drops of dish soap and two to three drops of red food colouring into the bottle.
Place 3 to 4 tbsp of baking soda into the centre of a tissue. Pull up the sides of the tissue and twist them together with your fingers to form a small bag.
Drop the tissue bag gently into the centre of the volcano and stand back. The volcano should erupt within 10 to 15 seconds.