Since I don't have a magic school bus like Ms. Frizzel, our class has to rely on models during science class. Today, a cork, a toothpick and a triangular shaped piece of construction paper became a model of a sailboat that I wanted to use wind power to get across the lake (the bucket of water). The problem was that it kept falling over, making the sail wet. What could we do to solve this problem?
After talking to their elbow partners, the students shared some of the ideas that they thought of or heard. One child suggested using plasticine to put two corks together. It didn't work.
Another put many corks around, but the teacher said that it broke the rules, because the single centre cork was the sailboat, and you couldn't add 6 smaller boats around it to keep it upright.
A little bit of plasticine around the bottom, almost worked, but the sailboat really wasn't able to catch any wind in this tipped over condition.
Finally, after at least 6 more inventive suggestions, a small broken toothpick was added to the bottom of the cork, and a small round ball of plasticine was added onto the end. Look at the result! What did the plasticine represent? What was it a model of?
Boats have keels. A keel is usually fin shaped and a boat can have small keels or large keels. They extend into the water under the boat to keep the boat from tipping over. They keep the boat stable.