How do islands form? Objective Students will be able to: 1.Define the vocabulary terms, tectonic plates, hot spots, and shield volcano 2.Identify the differences between the two types of volcano. (shield and composite volcano) Background First, we are living on a volcano, which is resting at the moment. Second, our volcano is on the move—it’s traveling towards China. About 1.5 million years ago, our volcano spewed forth enough lava to rise up out of the ocean and become “Tutuila Island.” Actually, just the tip of the volcano is visible to us—most of the volcano is underwater. While the tallest Duration: 60 Minutes.