This activity is intended to engage students in the engineering design process, focusing on two NGSS standards:
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.
Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.
A little history: in 2013, I attended Ella Miesner's presentation, Foundations for Fabrication, at FabLearn, a Digital Fabrication in Education Conference held each year at Stanford University. As I recall, she taught engineering design classes to grades 6-12. There, I heard something powerful. Instead of asking her middle school students to design something from scratch, she engaged them in the process of re-design. She also introduced us to the Pugh Chart (more below), which provided a structure to help students choose an optimal design. I was so excited, I did the lesson in my class that Monday morning!
I did make a few adaptations to her activity, which used objects such as a hair dryer and coffee grinder. I wanted to choose items that were more accessible to my students. To practice the "empathize" or "understand the end user" step, I went to my local CVS and picked up a tupperware lunch container. And, for redesigning, we tackled those zippered 3 ring binders that so many student carry and complain about!
LESSON PART 1: Modeling focus groups and establishing criteria (1-2 days)
We began by getting in to small focus groups and evaluating the tupperware container. Two students acted as recorders, and we made observations about the product's look and feel. Then students took turns using the product and we made observations about how they were used. Finally, we switched our point of view and considered ourselves a bunch of parents making additional observations. As you might imagine, those comments were mostly about safety and cleanliness!
Next, I modeled at the front of the room, how to sort the post-its into categories. I'd announce a note, and the students would decide if it fit in a category that was already on the board, or if it needed to start another category. Eventually, these categories became the criteria we woudl use to redesign this bowl.
Next, the students repeated this process in their own small groups, evaluating a 3 ring binder (someone in the group volunteered theirs.
We came back as a class, and each group shared their criteria on the board. As a class, we agreed on a list of five criteria that we will focus on for our binder redesign. For example, all classes focused on rings staying closed, other criteria included capacity, durability, safety, organization, and transportation (handles and such). I added the constraint that it must retail for $50 or less--so no jet packs, chrome corners, tablets, etc. :)
Finally, we watched the 8-minute ABC Nightline "Shopping Cart" video explaining the IDEO Deep Dive (if interested, there is also a longer version (3 parts). I like the video, but note that it is a little dated-- first aired in 1999!)
For homework, each student was tasked to do a technical drawing of their redesigned binder, considering our criteria and constraint.
LESSON PART 2: Re-design (1-2 days + additional prototyping time TBD)
The next class, students come together and (presumably) each have their own technical sketch. They then use the Pugh Chart to analyze each sketch against the design criteria. The reference binder they used receives a score of 0 (neutral) for each criterion. The first student presents his or her sketch, and the group assigns it a score of 0 (pretty much the same as the reference binder), +1 (an improved design as compared to the reference binder) or -1 (a worse design than the reference). Those are the only 3 scores, no +2s, etc. (Here is a LINK to a Pugh chart you can download and modify.)
Here are some student examples:
After (hopefully) objectively analyzing each design, students will realize that there is no one optimal design. Fort heir next step, they will add up the scores and choose one of the highest scoring designs. However, even that "best" design is unlikely to have received +1s for every criteria. So, wherever this "best" design is lacking, students can look to other designs to bring the best of each design together into on optimal design.
At this point, student groups can sketch out their optimal design, then build and present a prototype (their favorite part).
If you'd like to see photos of our "makerspace" (aka the science room) and some photos of other projects we've done, you can visit this slide show or read more at our Maker Club blog, Tales of a 3D Printer.