Most volcanoes just look like mountains, until bam! They erupt with either smoke and ash or lava. Engaging and accessible text describes and illustrates some of the most common ways that volcanoes form and erupt. Readers will be able to see how Earth's crust moves as plates, revealing the fierce activity of the layer below. Diagrams and cross sections of volcanic activity make the subject clear and easy to grasp. In a simple follow-up activity, readers model a volcanic hot spot in Earth's crust, mimicking the formation of the Hawaiian Islands.