You will need 1 can of play-doh, 10 pipe cleaners, a mini cup and approximately 10-30 pennies. We would like you to discover the strength of arched bridges by constructing a rainbow shaped bridge out of pipe cleaners and play-doh. You will attempt to balance a "pot of gold" (mini cup) on top of the arch and add pennies to test the strength of your bridge. Have fun and take a picture of your finished product. Don't forget to add your picture to your journal.