Over the course of 4 – 5 days, students design earthquake resistant structures based on their research of seismic design principles. Along the way, students utilize scientific text strategies, engage in scientific discourse based on evidence, experience the engineering design process and are introduced to the advantages of digital vs. analog signals. Components of this lesson connect to the following NGSS and Common Core Standards:
MS-ETS1-1 Define the criteria and constraints of a design problem with sufficient precision to ensure a successful solution, taking into account relevant scientific principles and potential impacts on people and the natural environment that may limit possible solutions.
MS-ETS1-2. Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.
MS-ETS1-3. Analyze data from tests to determine similarities and differences among several design solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success.
MS-ETS1-4. Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process
MS-PS-4-2 Develop and use a model to describe that waves are reflected, absorbed, or transmitted through various materials.
MS-PS-4-3 Integrate qualitative and technical information to support the claim that digitized signals are a more reliable way to encode and transmit information than analog signals.
On day one, students analyze text so that they can obtain and evaluate information (SP8) and engage in evidence based discussions (SP7).
Day two, students use a design matrix to determine which design solutions meet the criteria (ETS1-2) and begin testing their designs on the shake table.
On day 3, students begin to shake their initial prototypes and collect qualitative and quantitative data to create new design solutions. In addition, they work on generating questions and engage in scientific discourse as they explore connections to wave properties as the listen to the "song" or "sound a comet makes" that was collected by the Rosetta probe that landed on Comet 67P/Churyumov-Gerasimenko!
On day four, as students test their earthquake resistant structures they improve their designs based on the results (ETS.1). Moreover, students compare their results with other groups and designs to incorporate all successful components into a “super design” (ETS1-3). In addition, students are introduced to the difference between an analog and digital signal.
Day five of this lesson asks students to look at real world constraints and impacts. After developing their classroom prototype, students consider real world implications to society and the environment. They recognize that technologies have limitations and that while prototypes meet our societal needs and wants, they also have short and long term consequences. During this lesson, students further their understanding of analog and digital signals as the teacher takes the students through a visual model/analogy with a children's swimming pool!
Ask students, “What are you going to learn today?” Students should respond by stating something connected to the NGSS Essential Question (I keep this posted on my front board.). Thus, students might say, “We need to answer the question, what are the characteristic properties of waves and how can they be used in the world?” .
Explain that our focus over the next days especially lies in how waves can be used. Explain that scientists and engineers use data they collect from seismic waves to develop solutions in designing earthquake resistant building designs.
Remind students that they have been working on developing their scientific discourse. One key to a deep understanding of science is being able to generate questions founded in science.
Tell the students that you often try to make connections to scientific ideas outside of the classroom. Mention that you came across some information about a probe that had landed on a comet that immediately connected you to the EQ. The ESA’s Rosetta probe was able to land on a comet! While it had landed, ESA’s Rosetta probe detected cyclical changes in the comet’s magnetic field environment. To make the comet’s magnetic ‘song’ audible to people, researchers sped up the data 10,000 times its actual rate. Then, play the sound the probe detected for them.
Explain to students that as a scientist they must be able to generate questions (SP1) and make inferences based on their scientific knowledge. I might say something like “After listening to this, our first reactions might be to say, “Cool!” or “Awesome!” (Which it is by the way!), but as scientists we must not stop there. We must generate questions and inferences based on this new experience we just had. Many students think that a question is a sign that someone doesn’t understand. However, a question tied to the purpose of what we are learning can actually demonstrate deep thinking.”
To further explain scientific thinking, I might say, "Effective questions are founded in prior knowledge and application to new situations. Scientists take things that they know about science and see if they can apply those ideas to new situations they see in the world or use those ideas to find solutions to problems. Scientists can take their prior knowledge to make inferences about how and why phenomena are occurring. They can then take these questions to develop experiments (scientists) or design solutions to problems (engineers)!"
Say, “Using your prior knowledge about characteristic properties of waves and how they interact with matter, turn to a partner and develop a list of questions and/or inferences that you are making about what you just heard from the comet and waves. Think about the vocabulary, the relationships, the lab experiences, and even real world experiences involving waves, and think how those can relate to this new situation. Do those connections you make help you generate a question you’d like answered or help you make an inference you think might be true? Are there variables you could manipulate or an experiment you could design? Generate as many questions and inferences that are directly tied to the skills and Essential Question we have been working on together.”
Below are some questions that students generated:
Have students continue to work on the Seismic Design Principles Challenge. Remind them that prior to building they must come to you, their client, with the plan and be able to cite evidence of why their design meets seismic design principles that will insure their structure resist the shake. In addition, remind them that they must collect both qualitative and quantitative data for each structure in the data table on their lab sheet. In order for students to build their next prototype, they must show data and evidence of the improvements that they will be making.
At this point, students ask me if they can bring in extra marshmallows for their next prototypes. For me this works. Buying all new marshmallows for each prototype isn't financially doable. It is possible to reuse the marshmallows; however, it is definitely better to use fresh marshmallows. So, at this point I might say to the class, "An engineer in this class asked me if they could help fund the prototype by bringing in extra marshmallows. The answer to that question is, 'Yes!'. Just remember that there is a constraint of using 20 regular sized marshmallows on each design."
Here are some videos of our first shaking test, along with some things to discuss with students about their designs:
In this first clip, notice that at the end of the shake, the foundation is still standing. It is important that I ask, "Would my employees have survived?". I want students to recognize that though the base is still connected, this attempt does not fulfill the requirements.
In this clip, the students shake their structure and it does survive. However, this shake does not completely fulfill the requirements. This structure could not actually house my "employees" on the second flour. In addition, the top of the structure is not functional in the building. Thus, it is essentially an antenna. Students can make a roof in a triangle shape; however, they may not just add a really long triangle at the top to meet the height requirement.
After the first "shakes", students quickly learn that securing the bag of sand and preventing the mass of the structure from being asymmetrical are crucial. Students often alter their designs after watching the first shake. Just like the picture below, students start to add a sound foundation on the second floor to hold the bag of sand.
In the introduction to APPENDIX I – Engineering Design in the NGSS it states, "a commitment to integrate engineering design into the structure of science education by raising engineering design to the same level as scientific inquiry when teaching science disciplines at all levels." Engineering Design Performance Expectation ETS1-3 has students analyzing data for similarities and differences among several design solutions.
Ask each group to meet with another group and have each share their successes and seismic design principles that have been effective. As a result of data comparisons, students are expected to combine the successes of other designs to create a “super design” that utilizes the effective aspects of multiple designs.
Once the groups have paired up, ask them to assign one group to be Group A and the other to be Group B. Explain that each group will have 5 minutes to explain their design's important strengths and weaknesses. On the same piece of paper, have each group write the aspects or advice provided by the other group that they will consider using in their current or future designs. Having students record critical information serves a few purposes - it continues to develop them as "thinking" writers, and it makes them accountable to the conversation.