Designing a Solar Car Part 4
Lesson 4 of 7
Objective: SWBAT test original designs for a solar car in an attempt to answer the question, "Can solar cars be the transportation of the future?"
Part 4 of this lesson series is distinguishable from the others because the students are creating the physical cab of a solar car and testing to see how it works. I use a model by Pitsco as the base of the solar car. Students recreate their designs using Paper Mache. We blew up long balloons and used wheat paste to glue on tissue paper. The paste dried and students cut out the shape of their design from the balloon. We attached the cabs with popsicle sticks and taped on the solar panels. The tests were not as I had planned. I wanted to design an investigation with variables but the models I used were old and the parts didn't work reliably. There were too many variables out of my control. Instead the students had solar car races which was great fun.
Building the Model
At this point in the lesson it is time to build the aerodynamic cab to fit upon the chassis of the model. I have several of the Pitsco models built and I show the students the model. I explain, "The task is to use your design and build a cab to fit on this chassis."
The design constraints include the size of the chassis, the connection of the solar panel and the motor and the materials (toothpicks, popsicle sticks, and a variety of paper including tissue paper, tag board, etc.) I explain how we are going to Paper Mache a long circus balloon and shape it to match their design drawing solutions.
Students measured the dimensions of the car and blew up the balloon to create the model. They twisted the balloons and used rubber bands to shape the balloon before they glued on the paper. The students all wanted to use tissue paper to keep the design light weight.
In the movie below the students explain their designs.
Defending the Design
At this point students have acquired a lot of information about solar cars and they have created their original design. I use the strategy Write to Learn to pull all the information together in a Solar Car Design Defense to assess their understanding. Students must defend their design based upon their criteria. I ask them to write a defense of their design and call it a Technical Report.
I use a strategy called, Make a Rubric. In this strategy students use the criteria as the base for the rubric. We discuss what a design defense should look like. The students use their research for a citation (Solar Car Design Part 2), and the criteria (Solar Car Design Part 3). The students have created the rubric and we all understand how the work will be assessed. In this video, the students have share their Rubric suggestions and I review their ideas.
I create a Solar Car Design Defense Rubric Checklist. My strategy with the checklist is to allow the students the opportunity to self-assess. By making the rubric in a checklist format, I ask the students to check what they have done. As we are transitioning to Standards Based Reports, I place on the rubric the connections to ELA standards.
Finally I conduct a Gallery Walk. In a Gallery Walk the students move from one design to the next evaluating the design according to the criteria we developed in Designing Solar Cars Part 3. In the video the students evaluate one design. Listen for the spirited discussion about the aerodynamics of the design.
After Gallery Walk, students determined which they thought was the best design solution by walking over to the design they felt fit the criteria the best.
Testing the Designs
My intention was to design an investigation and test the models. Unfortunately the model itself prevented us from completing a test because the models did not perform reliably. The investigation would only test the quality of the model as opposed to the success of the aerodynamic design. Instead we went out side and had a race. It was great fun!
Because I did not perform an official investigation the Big Idea I asked students to consider our design problem, "Can solar cars be the transportation of the future? Why or why not? " I used a strategy called, Stand up for Your Idea. First students answer the question by writing three to five bullet points defending their answer. As evidence they used their design defenses as well as their experiences building and racing the cars.
I asked the students who believed solar cars will provide transportation for the future to stand on one side of the room and those who feel oppositely to stand on the other side of the room. The two teams tried to convince one another of their opinion. In the video below I introduce the activity and the students discuss their ideas. Forgive my horrible videography. Lots of chest shots, a few head shots but the conversation is important.