Share the video When a Volcano Erupts Underwater from PBS. Begin the video at the 2:34 mark to show students a pillow lava eruption. This video illustrates how lava cools into rock and how new land formations develop as the lava continually cycles through flow, cooling, hardening, and fracturing.
As students watch and discuss the video, introduce the term volatile as the lava flow paths changing rapidly and unpredictably. Have students record what they notice as the lava pushes through the crust.
Following the short video, discuss what students observed and how the underwater landscape has changed as a result of the volcanic eruption. Ask students to think about and predict what will happen once the pile of new rock reaches the surface of the water.
Introduce the NASA Lava Layering activity as a way for students to simulate the results of multiple lava flows, occurring in the same area over an extended period of time.
The procedure for the simulation can be found on page 79 of the NASA Educator's Guide. Students should complete the simulation in groups no larger than four.
Once teams have completed four eruption simulations, students should answer the questions on page 80 of the NASA Educator's Guide. The questions on page 81 can then be used for whole class discussion, relating the simulation in the classroom to the geological processes that occurred on the moon.
Following discussion, watch the YouTube clip Underwater Volcano Erupts Giving Birth to an Island. This news clip shows the creation of a new island off the coast of Japan, formed from the eruption of an underwater volcano. This video is a real world illustration of the constructive force of a volcanic eruption.
Once students have watched the video, have individuals or teams create a Venn diagram that compares the geologic processes they observed in the video to the simulation they completed in class.