Straw Bridge Challenge

This year I used the Straw Bridge Challenge on the first day of school as an ice breaker, an introduction to engineering, and a way to get their minds engaged.  There are several versions of this activity around, I used the one that was given to me by an engineer at Lockheed.

The Description

Goal:  Build a bridge that can span a 12″ gap and hold a 1lb weight for 5 seconds.

Materials:  20 straws.  24 inches of tape.  That’s it.

Design Specifications:  

1. The bridge must span a 12-inch gap between two desks.
2. The bridge must be free standing, meaning it may not be taped to the desk
3. The 1lb weight is a full 16oz water bottle.
4. The bridge must support the weight for at least 5 seconds without the bottle falling over and without the assistance of humans.
5. Only supplied materials may be used.  Nothing else.

The Advice

My first class struggled the most with it because I had no examples to show.  I was able to use my 1st classes bridges as examples for the rest of my classes, and the bridges got progressively better as the day went on.  You may want to have a couple examples available for the students to look at.  Although expect the a lot of the groups to try to copy the examples, rather than create something new.