A paper mache volcano is a time-honoured science fair project that children enjoy making and activating. Although many children create a plain paper mache volcano without any added detailing, you can make your volcano stand out from the crowd by making it appear more realistic. This can be accomplished by using arts and crafts materials, such as acrylic paint and red food colouring. This can potentially enable your paper mache volcano to win first prize at the science fair.
Combine 4 cups of flour, 2 cups of cornflour and 3 cups of water into a large bowl. Mix well with a spoon for five minutes until smooth.
Tape a paper towel tube standing up vertically onto the centre of a sheet of cardboard. Crumple up sheets of newspaper and tape them onto the cardboard, surrounding the paper towel tube. Tape crumpled balls of newsprint higher and higher into a volcano shape.
Tear newspaper into strips that each measure 2 inches wide, 8 inches long. Dip the strips one at a time into the flour and cornstarch paste and lay them over the mountain model. Cover the entire mountain form with six layers of paper mache strips (also spelt papier mache). Allow the paper mache mountain to dry for two hours.
Paint the paper mache volcano with acrylic paint to make it look more realistic. Use natural colours such as green, brown, white and tan. Allow the paint to dry for 1 hour.
Paint clear acrylic glaze over the entire paper mache volcano to protect the acrylic paint from wearing off or chipping. Allow the glaze to dry for 1 hour.
Pour 1/2 cup of baking soda into the centre of the volcano.
Combine 1 cup of white vinegar and 10 drops of red food colouring in a bowl. Mix the two substances for 1 minute with a spoon to incorporate them together. This will turn the vinegar bright red.
Pour the red vinegar into the centre of the volcano to allow the vinegar to combine with the baking soda, which will produce a baking soda eruption.