I call students to the gathering area. We review the last two lessons where we learned about Newton’s three laws. Today I am going to teach them about the engineering design process. We are going to use this process, along with our knowledge of forces, to design and build roller coasters in the rest of the unit.
I show students the poster in my room that defines the engineering design process. I choose to use the engineering design process from the Boston Museum of Science, as it is the easiest to follow and the graphic is great. You can find it at http://www.eie.org/overview/engineering-design-process.
I purchased this poster and I put it up in the classroom as we begin this lesson. In years past, I have made my own poster of the process. This is a cheaper option if you don't have the option to buy materials.
I review and define each step of the cycle.
1. ASK: Find the need.
2. ASK: Define the problem.
3. IMAGINE: Brainstorm to come up with ideas.
4. PLAN: Select the most promising design.
5. CREATE: Plan and manage the project.
6. IMPROVE: Build-test-refine the design.
I tell students that they will practice using this engineering design process in an engineering challenge today.
I tell students that they will be designing and constructing a paper card tower. They will have 100 3" X 5" index cards and 12 inches of tape to complete the project. The need/problem is that their tower will have to hold a small stuffed animal, for 30 seconds or more, at the highest elevation possible.
I tell students that they will need to go through the engineering design process, including brainstorming and designing their tower. A written record of the team brainstorm is required. A brief sketch of the adopted design will also be needed, prior to construction.
I hand students a group design process worksheet and give the a sample of each of the materials to help them decide on their design.
I put a timer on for 10 minutes and check in with students after this time. Some groups are usually ready to begin building, some still need time to refine their designs. I allow another 5 minutes before I warn them that their design team is going to result in cost overruns if they do not move on into the project phase. I give stragglers a minute to close their discussion and begin building.
Student build their designs. We do a team-by-team test of each tower. If the tower is successful and holds up the animal, we discuss what, if any changes could be made. If the tower is unsuccessful in holding the animal, students must improve and go through the cycle again. I allow successful student to act as design consultants in the improvement process.
I gather students in the gathering area to debrief the usefulness of the engineering design process and the pros and cons of their designs. This is often a venting time for unsuccessful teams, who may be very frustrated at having to redesign their tower.
I share with students that the tallest building, The Burj Dubai/ Burk Khalif, is the tallest tower in the world. During its construction, on the twelfth floor, it was discovered that the dimensions were very slightly off. Engineers calculated that is construction were allowed to proceed as is, this minor error would be so magnified at higher floors that the building would not stand. The engineers had to redesign the entire building based on this error to ensure that the structure would stand. I tell them this story so they understand that this is a real-world problem and not just a teacher-generated challenge.
We talk a little about the upcoming roller coaster challenge and the information we have learned in the last three lessons. All of these skills will come into play in the forthcoming lessons.