I engage students right away in the lesson by showing this website. This website shows current and latest earthquakes. We don't often hear about every earthquake, and most of my students are surprised to find out that earthquakes occur all the time. I spend a few minutes talking about the locations of recent earthquake and point out the distance to a plate boundary.
This lesson is very similar to yesterday's lesson. Yesterday students practiced building earthquake proof buildings. Today's lesson involves the engineering process of REVISING what was previously done in order to solve a problem.
I begin today's lesson by reminding students that they are engineers.They will revise their models of buildings from yesterday's' lesson and conduct an experiment to test how well their structures stand up under the stress of an earthquake. I remind them that students that this is similar to what some civil engineers do as their daily job. Students spend the first few minutes in their group discussing what they want to do differently from the previous day.
Next, I distribute 30 toothpicks and 30 marshmallows to each student. I tell students that the Earth has limited resources, so therefore engineers also have limited resources when building structures. I tell students that their structures should be at least 2 stories tall.
Student spend the next 25 minutes creating and building a structure. I remind students to think about their structure they created yesterday and work to improve and enhance their structure today. I remind students that their goal is to create an earthquake proof building.
You can see in this video a group revising their structure.
After about 25 minutes, I tell students that we will test their structures. You can see in this photograph below, I am helping place a structure on top of the jello, which acts like earth's crust.
In this video, watch as a student explains how the group revised their structure. He does a fantastic job communicating his group's thinking.
Each group has an opportunity to test their structures and present their ideas to the class.
To conclude this lesson I reinforce the concept that engineers design, test, REdesgin, and then REtest. I ask students to turn and talk with a partner about what went well with their design and what didn't go well. Next, I show this video, a fourth grade favorite since it talks about the tallest tower in Japan. The engineers in the video discuss the various ways they make the structure and tower earthquake proof. I remind students that even though we used toothpicks and marshmallows, they were working on a real scientific problem - creating earthquake proof buildings.