The last part of the design challenge involves making a model and defending the design. I use sharing strategies to share design ideas and to assess design ideas. The students share ideas as to help one another develop the best design idea. They must discuss the science content as a way to share their designs. After students draw a final design, the assessment sharing strategies give the students the opportunity to consider the criteria and give suggestions to improve final designs before I grade the designs.
Student have had the opportunity to get their designs evaluated. They now can choose the best drawing to solve the design problem. They have four different design drawings that have been evaluated by peers. My strategy is called Developing a Final Design.Typically the students have made changes to their designs. I ask students to re-draw their best concept on a large piece of graph paper. I ask the students to work in pairs or by themselves as they develop the final design to promote collaboration. Because inspiration can come at any time. I want the students to be able to ask one another opinions about ideas as they draw their final design.
I use a strategy called Six Stations to let students collaborate. I also use the strategy to support the students who want to work in pairs. When two students want to work together, I ask to see their designs because the partnerships have to be authentic. If they want to partner up, they must explain why they should be partners using the commonalities of their designs as rationale.
Sometimes students don't have similar ideas. After so much collaboration students get excited about a classmate's design. I allow them to find a partner with an idea they want to develop. If the designer agrees, the partner must re-draw the design they are going to develop. Together the two work on the computer to draw the 3D model.
There are students who want to develop their own design because they are loving the process. I allow changes at any time because change is authentic to the design process. I formatively assess the Nuclear Waste Final Model drawn larger. I look over the designs looking for weird dimensions or missing dimensions. Students use colored pencils to indicate the dimensions. so it is easy for me to see mistakes. After looking over the drawings, I send the students to the computer to start their 3D design.
The written component of this lesson is called Defending the Design. Students go back the the criteria we have developed. Students need to constantly be thinking of what defines a design solution. I ask students to make a bullet point summary of the criteria components identifiable in their design and how the criteria was met. In the Nuclear Waste Criteria Student Sample, the student has written the criteria and then writes a bullet point explaining how her design speaks to the criteria.
After organizing the information they feel is most important, students develop a Final Design Defense. They add the Design Defense to the paragraph they had written in Part 1 of the lesson, which address the question:
"Why is this an important design problem?"
I ask them to title the piece as a Technical Report, because it reports on a design solution.
At this point in the lesson, the students have developed their designs and have defended their designs. I like to use a strategy called Gallery Walk. Students have copies of their defenses and their designs. They lay out the papers on tables throughout the room. Using a bell, I allow a couple of minutes at each project. Students evaluate the project based upon the criteria. In the movie below the students are looking at the final designs. It is interesting to see how much they find is missing from the criteria.