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

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 Spaghetti Cantilever challenge is a fun one. Each team is given a small package of spaghetti, a roll of tape and a table. The objective is to construct a cantilevered structure that extends as far from the table as possible without touching the ground. The structure must be attached to the top of the table and nowhere else. Because spaghetti is very brittle, the engineering becomes very important. Measurements should be taken from the edge of the table to the furthest point of the spaghetti structure.
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