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Can you build a bone chillingly sturdy bridge?

Bridges are designed to support all those who would cross it.  Although a Bone Bridge should scare all who wish to cross, it would still need to support their weight.  Use cotton swabs, pipe cleaners, and popsicle sticks to build a Bone Bridge that will bear the weight of those who wish to cross.

Build a Bone Bridge in this STEM challenge that explores engineering!

 Background Information:

  • Earliest versions of suspension bridges were built by Thangtong Gyalpo, Tibetan saint and bridge-builder (among other things) from the 15th century. He built over 58 iron chain suspension bridges around Tibet and Bhutan and one of his bridges survived until 2004 when it was destroyed by a flood.
  • Before Industrial revolution (19th century), almost all bridges in use were made of stone. But wood and iron can resist tension and compression better and stone and United States had much wood so they made many wooden bridges in those times and most of them were truss bridges.
  • When compared, suspension bridges are often compared by the length of their main span (longest span they have). Akashi Kaikyō Bridge is the suspension bridge with the longest span in the world since 1998. Its main span has 1,991 meters in length and it connects Kobe and Awaji Island in Japan.
  • Many high schools hold balsa wood bridge building competitions. Balsa wood bridge building is an educational technology that is often used to promote subjects areas such as engineering, physics, static equilibrium and building trades.

The Challenge:

Build a bone bridge sturdy enough to hold the most pennies using the following materials.

The Materials:

  • Q-tips (30 – 50)
  • Pipe cleaners (5 – 10)
  • Popsicle/craft sticks/clothes pins (5 – 10)
  • Penny (to measure gap constraint)
  • Scissors

The Experiment:

  • Design a bone bridge that makes use of all the materials and is capable of supporting plenty of pennies.
  • The bridge must hover at least 1 inch off of the surface of a table.
  • The bridge must measure at least 1 inch wide.
  • Build the bridge as long as possible.
  • Bridge planks must be close enough that a penny can lie flat across them.
  • Send us your results.



Once you have finished this challenge, email our Youth Services Manager, Gina Knowlton,  Please include your first and last name, a picture of your bone bridge, and tell us how many pennies it held.

We will post any entrants experiments to our Facebook page on Thursday, October 29th!