Identify the criteria and constraints in a given engineering design problem.
Explain why it is important to specify criteria and constraints for an engineering problem.
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Engage (5 minutes)
Tell your students that you own an engineering company that makes paper airplanes. Someone has hired you to design and build a paper airplane that can fly as straight as possible. They need a
plane that can quickly get from one place to another without crashing. Show them the plane you built (see Prep Work section).
Ask your students to watch closely, and throw the plane.
What happened? Did anything go wrong?
The plane was supposed to fly straight, but instead it flew in loops or spirals.
Do you think the customer (the person who hired you to make the plane) will be happy?
No, they will probably be mad because you did not build what they wanted.
Why do you think this happened? Could this problem have been prevented?
Maybe you did not pay attention when the customer told you what they wanted, or maybe you did not test your plane after you built it.
Explain that today in class, you (the teacher) will be the customer and they (the students) will form paper airplane companies. As a customer, you will have some criteria for a good paper
airplane. Criteria are like goals or objectives. They define what the paper airplane (or in general, the solution to any engineering problem) should do to be considered "good" or "successful."
Each team will produce one final paper airplane design and demonstrate whether it meets the criteria. However, they will also face some constraints, or limitations. They will not have all day or
as much paper as they want to make their planes. They will find out the details for the criteria and constraints in a few minutes.
Recommended: if you have a lot of students who have never made a paper airplane before, walk the whole class through building a simple design, one step at a time. You can use the basic or
intermediate designs from our paper airplane instructions handout, which is available to help students get started with
some different designs.