Flyin'   Concrete

You may think that frisbees are an invention of the 20th century…but that myth can be put to rest.  We can actually trace the origin of the frisbee back to the time of King Arthur and his Knights of the Round Table.  Apparently, during a meeting of the knights, Arthur and his noble warriors needed a plan to defend the kingdom against invasions from the Celts…then known as the "Beads" because of the elaborately adorned head peices they wore on their raids.  The knights devised a plan to hit the "Beads" where they could be hurt…in the head…and decided that large flying stones would do the trick.  To gain an advantage by hurling many large stones at once, the plan was to use "flying" stones that could travel fairly large distances when thrown by hand.  This way, the army could "freeze" its enemy from a distance and pound them vigorously before engaging in hand-to-hand combat.  The Round Table gave the knights the idea to form disks out of mortar and, thus, the first "Freeze the Beads" was born into existence.

Over the years, the evolution of the frisbee has brought longer distances and safer, more controlled flight.  Still, the idea is to produce a disk that flies level and allows for tremendous accuracy of targeting.  Lighter materials and the invention of plastic brought Wham-O™ to leadership on the frisbee frontier.   We will transport ourselves "back in time" to the days of the Knights of the Round Table to experience the discovery of the frisbee.  In this endeavor, we wish to learn about the problems they encountered while trying to form moldable products that would harden into a durable flying disk.  Your task is to design and build the strongest, lightest, best flying, best looking cement disk that you can possibly make in four days.  To do this, you will need to

•  Decide what materials you will need
•  Formulate a "recipe" for your disk
•  Decide how to make it light but durable so it doesn't break easily
•  Decide how to make a form and mold it into a "flight-worthy" shape
•  Make it and have it ready within two days for testing
•  Test it with the class

You may use any materials you want….but the majority of your disk must be cement or concrete. You may use any means to mold your disk to the desired shape…but it needs to be done in class, not at home. You will be evaluated by the teacher and by the class based upon the following categories:

1.  How well-made is the disk?
2.  How well does it fly?
3.  Is it durable for multiple flights?
4.  What is its Weight:Distance ratio?
5.  Project Report discussing all procedures and reasons for design.

Accept this challenge to be "One" with the Knights of the Round Table!

Good Luck and Good Flyin'!

*The validity of this "historical" information may not be accurate!!

See students making, testing, and researching the making of concrete frisbees.

In this unit, we spent 2 weeks learning about the differences between cement and concrete, what it is, how it is made, what factors influence the making and use of concrete, and this final design project. You can find more about what we did by visiting the materials research site at the University of Illinois where much of our material originated.

Click on an image for a larger view.

Beth checks the ingredients while her partners make a mold.	Mixing concrete	Measure
Tape and form	Here's how we test the concrete for strength to determine which formula is strongest.	Snap!
Adding weight to the lever.	Time for some more recalculation	Using rubberbands to reinforce the concrete. Interesting idea.
		This frisbee is nice and light...but a bit too fragile. No reinforcement.
Nice job, guys.	A little chiseling work to smooth it out.	This really does LOOK like a frisbee.
Mr. W is testing the frisbees.		Kevin is going to throw this one
Let it fly!	Jason shows where it landed.
Caught in the act!	The final result...didn't fully stay together.	But this one did. Good Job, Bex.