The Wind-Powered Rescue Car
Free · 8 scenes
At the town's Ready-for-Anything Making Day, your mission is to deliver a red practice pouch to the far tent in three tries. Mio holds out the design card. “Maker, you are our design leader today. I will build the car and race it.” For the first time, you are responsible for choosing how the team moves forward. You take a deep breath and nod with Mio.
You reason that catching more wind will make the car faster, so you choose the large sail. Mio fastens it, and the first whistle blows. WHOOSH! A crosswind catches the tall sail, lifts one wheel, and tips the car into the safety straw. The cheers stop, and your chest tightens. Mio looks from the fallen car to you. “That was not what we expected. Let us find out why it tipped.” There is no blame in her voice.
A curved tire track. A wind ribbon streaming to the right. Wheels set close together. A pouch strapped high. Mio points to the clues. “Where should we start, Maker?” You separate the trouble into two problems: tipping and sideways drift. Then you decide to make it harder to tip first.
Following your plan, Mio spreads the wheels wider and straps the pouch low. On the second try, the car does not tip. But the large sail pushes it right, farther right—until it hits the safety straw one handspan from the goal. One try remains. Your palms turn damp, and Mio wipes her eyes. “We were right about stopping the tip. Sideways drift is the problem left.” Instead of closing the record card, you open its final line.
On the workbench are a large sail, a small sail, and front wheels that can change direction. The workshop teacher sets down a small fan. Out on the course, the ribbon points sharply from course-left to course-right. Car Two's tracks also curve toward course-right. Mio lifts the two sails. “How should we combine a sail and a wheel direction?” You do not know the answer yet. Only one final run remains, but you can test as many times as you need.
Read the wind and complete the final car
Mio will build it; the design leader at the screen will decide. The car gets the same forward launch every time. The real course crosswind blows from course-left to course-right. You may also test the opposite wind. Sideways drift is enlarged so the differences are easy to see. Finish by finding the sail and front-wheel setting that fits the wind you observed.
The workshop teacher sets a fan beside the crosswind test lane. The car will receive the same forward launch every time. Mio places the rebuilt car down and looks to you. “I will assemble it. You, the design leader, will read the wind and decide. We will watch how it moves and revise together.” You have only one final run. Here, you can verify the last design first.