Our first Engineering Challenge for kids got off to a fabulous start with a program about designing sails. I had experienced this activity for myself at conference on science education, where it was presented by members of the Boston Museum of Science team for Engineering is Elementary. This activity is lesson 3 of their Catching Wind unit.
For a setup I built a “boat” out of a piece of styrofoam and taped drinking straws underneath it. I then strung fishing wire through the straws and taped the fishing wire between two tables. This created a stable boat that would slide along the fishingline. I made two small holes in the middle of the boat just large enough to stick a popsicle stick into. The original program instructions suggest creating only one hole so that the popsicle stick can only be inserted facing in one orientation, but the styrofoam was flexible enough that I felt comfortable making two holes so that the stick could face either direction. This seems like a lot of setup when you could just put boats in water, but there’s a method to the madness. By creating a very prescribed boat scenario, we cut down on a lot of variables. The boat can’t go sideways, or have a piece fall off, or catch the wind at a slightly different angle every time. The only thing that will change from trial to trial is the design of the sail, thus reinforcing that child designer is in complete control of what is going on.
Before the program started I cut small squares out of each of our materials which included tin foil, felt, wax paper, tissue paper, and construction paper. I gave each child a package with these small pieces and we examined them together as a group, discussing their properties and how those properties might affect its usefulness as a sail. Providing trial samples of the materials instead of examining the large pieces we intended to use for actual construction was suggested by the Engineering is Elementary team to help allow the children to explore the materials without getting distracted by trying to jumpstart the building process or possibly ruin fragile materials like tin foil by exploring the range of possibilities the materials present.
After walking through an exploration of the materials, we talked about sails, sailboats, windmills, and what factors we thought might be important to catching the wind. After about fifteen minutes we were finally ready to start building. I handed out the sail materials, markers, masking tape, and popsicle sticks and the children got busy.
There was quite a wide range of ages for the program. The original challenge, simply get the boat to sail from one side to the other was a struggle for some of the younger children, while the older kids were able to design an efficient sail almost immediately. I encouraged everyone, even those who had been successful, to go back and redesign their sail to see if they could make it even better. One of the teen boys asked how we’d know if they’d made it better, and I suggested using speed to determine success. I ran upstairs and got my stopwatch so that the students could compare their first boat and second boat.
Timing the boats turned out to be a great idea. The noncompetitive kids were so engrossed in their own work that they barely noticed that other kids were also timing their boats. But there was also a large section of kids who quickly turned it into a friendly contest, designing and redesigning over and over again to shave a second or two off of their best time. I had been encouraging parents to participate, and now that there was a competition aspect, I had whole families competing with each other to see if Mom or Dad could build a faster boat than their child. My favorite was a family with boys about 8 and 12. When their older teenage brother came to see if they were ready to go, he got sucked into trying to beat his younger brothers. Then the grandfather came down to see what was taking so long, and he challenged the whole family that if they could beat the boat he was going to build he’d take them all out for ice cream. The boys won.