Hi, I thought you may like this Mentalrobics exercise from Braingle.com:
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Engineering Challenge : Egg Drop

Engineering challenges are fun activities that are frequently assigned to students in physics or engineering classes, but they can easily be used outside of these venues. An engineering challenge usually has a simple goal and some rules about what sorts of materials you are allowed to use. These are great ways to get people thinking creatively and to foster teamwork and competition. Try an engineering challenge at a birthday party, office outing, scout meeting, or any other gathering where you want to have fun and exercise your creativity.

The Egg Drop is one of the most famous engineering challenges. Each team is given a raw egg (sometimes light bulbs are used instead) and a small amount of simple building materials such as toothpicks, popsicle sticks, glue, rubber bands, paper, tape, etc. Each team should use the same materials. The teams must then build a device that will protect their egg from a drop of a specified height (at least 10 feet). Set a reasonable time limit and have some small prizes for any team that succeeds in creating something that will protect an egg from breaking upon landing.
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