Spaghetti Bridge

Shared by Girl Day Presenting Partner: BASF Corporation

Recommended Grades: 6-8

Goal: Design and build a bridge that can support a bag of sugar (or something else of similar weight) using spaghetti, rubber bands, and tape.

Materials:

  • Dry spaghetti
  • Rubber bands
  • Tape
  • Bag of sugar/something heavy
  • Two tables close together/four cans/etc to hold the bridge
  • Paper
  • Pencil
  • Newspapers or a tub to catch falling material

Procedure:

  1. Draw out your bridge design on a piece of paper. 
  2. Build the bridge using spaghetti, tape, and rubber bands. 
  3. When the bridge is complete, test its strength. Place a bridge so it spans across the gap between two tables (or elevated on four cans). Place newspaper and/or a tub below the bridge to catch any falling debris.  
  4. Place the bag of sugar (or something similar) on the bridge. If the bridge can support this weight, try adding additional small items until the bridge breaks. 
  5. Re-design your bridge and re-test. Were you able to make your bridge stronger? 

Guiding questions: 

  1. How strong was your initial bridge? Did it perform as you were expecting?
  2. What factors did you consider in re-designing your bridge? Adding height, stronger base, etc. 
  3. How could you further improve your bridge to hold even more weight?

STEM Connections:  Many different types of engineers work together to build bridges that span spaces and sometimes reach for the sky: civil engineers do most of the design and construction, but they work with mechanical engineers, material engineers, and even environmental engineers to design structures that are stable, safe, and sustainable. When designing a bridge, many factors must be considered, such as: the length of the bridge, the amount of weight it needs to hold (how many cars will be on this bridge during rush hour?), where is the bridge located (is it near water?), what materials are available, will be able to last in this climate, and are good for the environment. and finally, how much does all of this cost?

In the activity today, we used the engineering design process:

  • Ask - what is the problem and what are the constraints (what materials are available)? How strong does the bridge need to be and what materials can we use to build it? 
  • Imagine - think of possible solutions
  • Plan - draw out the bridge design
  • Create - build the bridge
  • Improve - make the bridge stronger

For more ideas, check out this video