Although there is some variation between specific preschool volcano projects, most use very similar materials. You will need two sets of items -- one set for the actual volcano structure itself and the other for the erupting lava. The volcano can be as simple or complex as you, and your class, would like. The basic items necessary include a paper cup (the larger the better), tin foil and modeling clay. You may also choose to add small, plastic toys, such as trees or dinosaurs. To make the erupting lava, you will need baking soda, white vinegar and red or orange food coloring. Make sure to have a foil cookie sheet or plastic tray handy to place the volcano on. This will act as a base for the model and help to contain the mess.
Chemistry may not be the first thing that comes to mind when you think about volcanoes, but this preschool project combines more than one area of science. The baking soda and vinegar lava shows young students how, when mixed, different chemicals can react to form a byproduct. Although preschoolers will not yet be able to understand the intricacies of the acid-base reaction or that the baking soda and vinegar neutralize each other to form carbon dioxide, they can recognize the basic concept of change.
Creating a three-dimensional volcano teaches preschoolers about the artistic process while helping them to better understand the geology of our planet. Start by placing a cup with the opening facing up on a flat surface, such as a cookie tin or tray. Invite the children to help mold layers of foil around the cup, forming a mountain shape. Compare this to a triangle with an opening at the top. Have the children flatten pieces of clay with their hands or a rolling pin. Press the clay against the foil mountain until it sticks.
The model volcano in itself makes a cool classroom project, but it won't compare to the surprise and delight that your preschoolers will get from erupting lava. Have the kids measure 3 teaspoons of baking soda and 1 cup of white vinegar. Encourage the children to pay attention to the numbers in the measurements as an added lesson on math. Squirt a few drops of red or orange food coloring into the vinegar for a lava hue. Place the baking soda into the cup that sits in the center of the clay volcano. Gather the children around the project and make sure that everyone has a clear view. Ask the children to predict what might happen. Add the vinegar and watch as the both the ingredients and the children react. The mixture will begin to bubble and foam out, covering the volcano for the next few minutes.