Locate an Earthquake’s Epicenter Lesson Plan: Earthquake Game

Lesson Procedure:

1. Begin the lesson by asking students what they already know about earthquakes. Here are a few discussion starters that will help you assess prior knowledge. You can jot their responses on a concept map.
   • What is an earthquake?
   • What causes an earthquake?
   • What is the epicenter of an earthquake?
   • What is an aftershock?

   • How might a scientist predict an earthquake?

2. Build students knowledge of earthquakes by playing the BrainPOP movie Earthquakes to the whole class on the whiteboard or other display. Pause the movie as needed when Tim explains the concepts of an epicenter (time code 02:00), seismic waves (02:20), and aftershocks (03:03).
3. Project the Earthquake Game. Tell students that the objective of this game that they will play is to locate an earthquake’s epicenter, or source. Explain that an earthquake’s source can be found using triangulation -- a process in which three locations are able to report the time the earthquake was felt.  Additionally, by measuring the delay between primary (p) and secondary (s) waves, which move at different rate through earth, they can determine the distance to the epicenter.  Play through the Demo version of the game, which reviews the concepts of shockwaves, epicenter, and how to figure and earthquake’s source.
4. Now open the game’s “Free” mode on the whiteboard. Give a tour of the game’s interface, showing how to use the timeline at the bottom. Demonstrate how the timeline matches up with a city by representing the times the city felt the earthquake. Model how to click and drag from the center of a city to line up the location radius tool with that city’s position on the timeline. Repeat for all three cities and prompt students to make observations about the circles. Ask Where do the circles intersect? Place the origin at the point where the three circles intersect. Ask What does this point represent? (the earthquake’s epicenter). Ask Why do you think this process is called “triangulation”?
5. Now click the “Game” mode. Call on students to come up to the whiteboard and identify where the epicenter might be. If students answer incorrectly, remind them to look at the timeline to try and figure out why the answer is not correct and what needs to change to figure out the right answer. Alternatively, invite a second volunteer to help the first. You can also scaffold by using the radius tool for one city and then have the student guess. Repeat the process until students identify the correct origin. Ask students how they know it’s correct. Encourage a class discussion by asking how they think seismologists use this process to locate the origin of an earthquake.
6. Divide the class into pairs or small groups to play the Earthquake Game on their own.Circulate as they play, only helping as needed. Observe their progress,  listening in on strategies.
7. If students have individual logins through My BrainPOP, encourage them to use the SnapThought® tool to take snapshots during game play, and reflect on their discoveries. For suggested prompts, see Earthquake Game: SnapThought Prompts.
8. Circulate as students play and help as needed. When most of the class has reached the “combining waves” part of the game, have students pause for a brief discussion about the concept of noise cancellation. Ask then how they think noise cancellation works. Give them a chance to respond, and make sure they understand that combining two opposite waves causes them to cancel out. Ask students, for example, to think about how this might play a role in noise cancelling headphones. To go deeper into this concept, if time allows, discuss the concept of interference, which they can read about in the In Depth Related Reading that is part of the Waves BrainPOP topic.
9. Bring the class together to discuss what they learned about earthquakes, including how to locate the epicenter. If students are using SnapThought, encourage them to share their reflections.