Learning Using Various Models

The students at the Academy of Aerospace and Engineering are focusing on the use of models this week, though we use models throughout the school year in various ways. A model can be physical, conceptual, or mathematical, and we use all three types. The use of systems and system models is also one of the cross-cutting concepts promoted in the Next Generation Science Standards, the latest guidance on how to teach science effectively.

For the 7th graders, Ms. Garavel introduced the idea of models, then gave the students an assignment to assemble a model aircraft or spacecraft, do a report on it, and present it to the class. The students will also soon be flying model gliders, then designing their own model gliders. These students are learning that models can be a simple way to learn about a complex machine, such as an airplane. They are also learning some basic techniques for building. While the assignment and tasks are fairly simple, they serve as a good model for later on when the students learn to build in our makerspace using hand tools, power tools, and 3D printing. The following photos show the 7th graders assembling their models and preparing their reports.

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I am teaching the 8th graders, and we are using model rockets to study motion, primarily the concepts of distance and displacement, speed and velocity, acceleration, and force. The students had to design their model rockets to accelerate as much as possible while all using the same model rocket engine. After some preliminary labs where we studied motion, we discussed how we could graph a model rocket’s motion when it is launched. A graph is a mathematical model. The students saw how a velocity vs. time graph could be used to find the altitude of the rocket by calculating the area under the velocity curve. We also used a wind tunnel to model how drag will affect the rocket inflight. The following photos show model rockets and the 8th graders building, testing, and launching them and measuring their altitude and time to reach altitude – and to show how much these students have progressed in the past year, note that a student is running the launch pad (and he did a superb job, maintaining a safe, efficient launch schedule), and all the students’ rockets launched and flew straight, stable flight paths, compared to a 50% success rate the first time they did such a project last year.

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Finally, in the last two weeks the students have heard guest speakers who serve as role models. In celebration of the US Air Force’s birthday, we heard Captain Nicole Robillard, US Air Force, speak via Skype about her service as the supervisor of airfield operations at her base in England. I met her there when I was traveling in England this summer, and what struck me was this very professional officer was from Bristol, Connecticut. What was especially impressive was that she and her three sisters all attended the US Air Force Academy, an extremely selective college. We also heard another guest speaker this week, Donna Men, a senior at Western Connecticut State University majoring in accounting. Donna was inspirational as a role model, as she had moved to this country from Cambodia when she was ten years old, speaking no English. She went on to become a successful high school student (and my student for three years) who earned so much scholarship money, she got a refund from WestConn every year. She also has already gotten a job offer from Deloitte, a world class accounting firm. These role models and the other forms of modeling are helping the students at the academy become better learners and better citizens.

What the NGSS Doesn’t Say: Students Learn from Failures

At the Academy of Aerospace and Engineering students have been using model rockets as a medium for learning all aspects of science, technology, engineering, and math (STEM). First they studied the science of rocketry and its history. They also compared rockets and rocket engines to what they had learned about aircraft and jet engines. They learned how to measure altitude using basic trigonometry, a new type of math for them, but related to what they already knew. They did a science lab where they compared the performance of two different commercial model rockets. Then they did an engineering design challenge where they chose one of the two commercial model rockets and improved its design to make it fly higher. This challenge ended with launch tests on May 26th, followed by a class discussion and an analysis of the results. Six student crews (groups of 4 to 5 students) had each redesigned a rocket, changing the body tube, fins, recovery system, and/or nose cone to reduce weight and drag. Out of the six rockets, four achieved the goal of flying higher than the average height achieved by the commercial rocket, as measured during the science lab. One of the six proved to be unstable on launch and went out of control, tumbling end over end and not flying above about 20 feet. One blew up on the launch pad because it would not fly up the launch rod due to faulty construction. Because we had followed the Safety Code of the National Association of Rocketry, everyone was well clear of the launch area and nobody was ever in any danger from these mishaps. Therefore, four crews achieved success, and two crews failed in their design. I told the students I was glad these failures had happened…what?! Let me explain why.

The Next Generation Science Standards (NGSS), which were adopted by the state of Connecticut this year and guide our curriculum, have a major section dedicated to engineering design. I incorporated these standards in the academy curriculum as I wrote it last year. Here are the standards for middle school students that I use:

  • ETS1.A: Defining and Delimiting Engineering Problems
    • The more precisely a design task’s criteria and constraints can be defined, the more likely it is that the designed solution will be successful. Specification of constraints includes consideration of scientific principles and other relevant knowledge that are likely to limit possible solutions. (MS-ETS1-1)
  • ETS1.B: Developing Possible Solutions
    • A solution needs to be tested, and then modified on the basis of the test results, in order to improve it. (MS-ETS1-4)
    • There are systematic processes for evaluating solutions with respect to how well they meet the criteria and constraints of a problem. (MS-ETS1-2), (MS-ETS1-3)
    • Sometimes parts of different solutions can be combined to create a solution that is better than any of its predecessors. (MS-ETS1-3)
    • Models of all kinds are important for testing solutions. (MS-ETS1-4)
  • ETS1.C: Optimizing the Design Solution
    • Although one design may not perform the best across all tests (my underline), identifying the characteristics of the design that performed the best in each test can provide useful information for the redesign process—that is, some of those characteristics may be incorporated into the new design. (MS-ETS1-3)
    • The iterative process of testing the most promising solutions and modifying what is proposed on the basis of the test results leads to greater refinement and ultimately to an optimal solution. (MS-ETS1-4)

What these standards do not specifically say is that a design may fail to solve the problem. In other words, the student should expect that a design not only “may not perform the best across all tests,” but it might actually not perform at all — it might be a complete failure, as two out of the six rocket launch tests were. But what failure shows in stark reality to students is that the design did not work, and if this lesson is emphasized correctly, students will learn much more and remember the lesson much better than if everything worked and went smoothly. How did I do this with the rocket failures? I first have told the students all year that failure is part of the journey to success. We looked at many real-world examples, especially the record of SpaceX’s attempt to bring a rocket back and land it after launch. In December, right after SpaceX had achieved success in this attempt for the first time and after many failed attempts, we had a guest speaker, Eric Womer, who was a graduate of our middle school and is now a propulsion engineer for SpaceX. He explained very clearly how SpaceX and its founder, Elon Musk, have persevered through many failures to achieve success. Throughout this school year, my students have done several engineering design challenges, and in each one, some crews succeeded and some failed in their initial designs. Each time we discussed the results and learned from them. Now students are used to failure as a normal consequence of trying something new.

Yesterday I attended the graduation of my oldest son from Rensselaer Polytechnic Institute. One of the speakers at the graduation was renowned physicist, Steven Weinberg. The gist of his speech was that he learned the most in life from the times he was completely wrong about something. He gave a few examples, but essentially he was saying that he had learned from his failure to understand something correctly. In seeing his failure, he had been forced to reexamine what he had believed to be true, then he started over and rebuilt his beliefs. This is the same process as an engineer follows when a design proves to be a failure. In all cases, failure is just one of the expected steps on the road to new discoveries and ultimately to success. We are learning this at the Academy of Aerospace and Engineering, and maybe someday it will be in the NGSS.

Here are photos from the launch tests:

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Six Redesigned Rockets Ready for Launch
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Successful Launch Begins with Good Ignition and Flight Up the Launch Rod
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Successful Launch Clears the Launch Rod and Flies Straight Up
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Successful Launch Climbs Straight Up (Curvature Due to Wind)
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Watching a Successful Launch
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Rocket Fails to Launch and Blows Up on Pad Due to Faulty Construction

Seismograph Challenge: Incorporating Engineering Design into Science

At the Academy of Aerospace and Engineering, our 7th grade students are studying earth science now, with a focus on plate tectonics, earthquakes, and volcanoes. To connect this topic to our aerospace theme, we are looking at how scientists use remote sensing with aircraft, spacecraft, or remote ground sensors to study earth science. Since another theme of our academy is engineering, I also try to have some sort of engineering design challenge with every unit. This is right in line with the new science standards:

“The Next Generation Science Standards (NGSS) represent a commitment to integrate engineering design into the structure of science education by raising engineering design to the same level as scientific inquiry…students are expected to be able to define problems—situations that people wish to change—by specifying criteria and constraints for acceptable solutions; generating and evaluating multiple solutions; building and testing prototypes; and optimizing a solution.” (NGSS Release, April 2013)

Therefore, this past week, I gave students the challenge to design and build a seismograph, the device used to detect and measure an earthquake. Students learned how seismographs were first developed, how they have been used, and some simple ways to make one. They took these ideas and developed their own designs, then they built prototypes, then we tested them in our Makerspace by using a workbench as our “Earthquake Test Center.” It was a fun project, and all of the seismographs registered “earthquakes,” both large and small – we pounded on the workbench to simulate a large earthquake, and we wound up and released a little hopping bunny toy to simulate a small one. Here are photos of each crew (student group) and their design:

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Here are photos of students testing their seismographs before the big test:

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