Engineering Design - Toothpick Bridge


Design Statement

Design and build a wooden toothpick bridge that will span 50 cm and support increasing weights.


The bridge must be constructed from standard, round or flat, wooden toothpicks. Glue will be used (wood glue or latex glue) to hold the bridge together.

Additionally, your instructor may provide you string, masking tape and other materials to aid in your construction.

Bridge limits: length 60cm, width 15cm, and height 15cm

Bridge must not extend more than 10 cm onto the supporting surface.

Masses will be used to test the strength of your bridge.

Testing Conditions

Masses can be used to test the structure, or a hooked bucket can be attached to the bridge where sand will be added to increase the weight.

Your instructor will provide more details on how the bridge will be tested.


1) What factors increased the strength of the bridge?

2) Does a heavier bridge automatically mean it is stronger?

3) What points on the bridge seemed to be able to hold the most weight? Where were the weak points?

Possible Extensions

1) Bridges can also be build using spaghetti or straws, though they probably won't be able to support as much weight and may require more of a suspension style design

2) File folders can also be used: See Designing and Building File Folder Bridges