1. Assign groups and roles by telling students that they will be working in small groups (2 to 3) of "architects" and that they will be designing structures that can withstand earthquakes. There are many different roles that you can assign the members (Recorder, timekeeper, etc.) Since there will be only 2 to 3 students in the groups, it may be good to assign students with multiple roles, or if you have a larger classroom, you may increase the size of the groups as you see fit.

2. Inform the students that the activity will be a competition that will determine which team can construct the "best" earthquake-proof structure and that individually the members of the group will answer the questions:

• What do you think engineers and architects build into their structures to minimize the damage caused by earthquakes?
• What factors do they consider? (List at least two)

At the end of the activity, groups will share their responses. Before they begin, inform them that they need to consider the following four factors:

1. Distribution of weight
2. Variation in shape
3. Variation in height
4. Composition of materials

3. On a blank piece of paper, students work together to sketch out a basic design for their structure and be prepared to give a rationale for the design decisions that they make and be prepared to answer questions at the end. The design must meet only two requirements:

1. Must be four levels of toothpicks high, point to point.
2. Students MUST use a combination of the clay and the toothpicks

Remember: Students are not building walls for the structure, but merely a wire frame. Consider a radio tower as an example. Students should have at least twenty minutes to sketch and build their structures before they are ready to test their strength. Have tow teams bring their structures next to each other so that they have exposure to different designs. One group's structure will be labeled design "a" and the other design "b." To test the structures, place them on top of the shake tables and secure them to the top of it using the scotch tape. One person on the team will be responsible for producing the "earthquake." To induce shaking, grasp the bottom portion of the binder and gently, but deliberately move it back and fourth to produce a steady level of oscillation. Time each "quake" for thirty seconds and record observations. One team will being their shaking while all students will observe for the thirty seconds, then the second team will induce the earthquake of their own. If a structure withstands the entire length of the thirty seconds, continue shaking until the structure no longer stands.

4. Record observations.

5. After the shaking has been completed. Have the students answer the following questions individually:

1. Which structure withstood the quake better? Why?
2. What part of the structures sustained the most damage?
3. Where were the breaks (if any) in the structures?
4. Explain how you might consider the "four factors" when building a structure in an earthquake prone area like Northern California. How heavy or tall should a structure be? What shape and what kind of materials?
5. What kind of building would you not want to build in the Bay Area of California?
6. How would you improve your structure if you were to build it again?