California is a volcanic wonderland with examples of nearly every volcanic feature found on the earth. This lecture will introduce the students to the theory of plate tectonics and how this theory accounts for development of California’s volcanoes. Through a multimedia presentation and illustrative activities, the students will learn to identify the different volcanic features and where to find specific examples of most of these features within a short drive of Livermore. This lecture will also address the volcanic hazards associated with each of California’s volcanoes in the context of their historical activity and anticipate future activity. Volcanology is a very young science having undergone a tremendous transformation in the past 50 years. Students will also be exposed to the history of volcanology and presented with some unanswered questions presented by California’s volcanoes. This is the fourth presentation in this year's Science on Saturday lecture series. The series is co-hosted by LLNL's Science & Technology Education Program and Sigma Xi.