Why would you? I don't know. I'm assuming you are referring to making a model of a volcano. I don't know that a real one has ever been made. You might want to make a model to demonstrate to your class or school how volcanoes operate. But I wouldn't recommend this as volcano models have been over done as science project. But if you just want to have fun, go ahead. You can use paper mache or modeling clay to create your structure and the old vinegar+baking soda formula always produces a good eruption. Add some red food coloring for a better effect.