We'd like to share our latest design challenge with you all.
*For the Teacher Contest, the learning objectives of this exercise were that in the building, racing, and development of their Zippers, students would have an opportunity to practice language structures covered in English classes that week - the past simple and present perfect - within a meaningful context.
Zippers are simple devices to make, and can be made by anyone who can use sticky tape and blow up a balloon.
You'll need a drinking straw or two, a balloon, scotch tape or similar, and a length of cotton thread.
To make a Zipper:
1. Cut the drinking straw in half
2. Using sticky tape, secure one half of the straw in a position passing through the neck of the balloon - blow up the balloon through the straw to test your seal
3. Tape the second half of the drinking straw to the first - make sure that both ends of this second straw section are open
4. Tie a 10 meter length of cotton thread to a suitable anchor, then make a loop in the other end of the thread. Hook the loop over a suitable latch / nail / twig / etc, in such a way that it keeps the cotton thread taut
5. Unhook your loop and pass the thread through the second half of the drinking straw, then re-hook the loop again... suspending the Zipper on your cotton thread
6. Blow up the balloon while it's hanging on the thread
7. When the balloon is inflated, let it loose, and it will move along the thread
Set up 2 or more threads for races and refine designs based upon repeated winners.
Improvements include using flexible straws to angle the balloons away from the cotton thread and to adjust the angle of the leading edge of the carrier straw, flaring or belling the leading edge of the carrier straw, using different types of thread... eg fishing line, changing straw and balloon sizes, etc, etc.
There's lots of room for students to think through improvements, and the simplicity and ease of construction allows for a fast turnaround of remodeling and testing of ideas.
Enjoy :D - and Merry Christmas!