This very simple STEM challenge is a great way to find out why arches are such an important structural shape. Bridges often have arches to make them stronger and more stable. The arch shape allows any load on the bridge to be spread outwards along the curve of the arch.
Pont du Gard is a brilliant example of a bridge constructed of arches.
Paperclips or other small objects
Set up two piles of books the same height with a small gap between them.
Place a sheet of paper over the top to make a bridge.
Carefully place paper clips on the top until the bridge collapses.
Record the number of paper clips added before the bridge collapsed.
Remove all the paper clips and bend the same piece of paper into an arch shape between the piles of books.
Add paper clips again until the bridge breaks.
Can you add more paper clips to the arch shape or the flat bridge?
You can see that the arch shape tolerates a lot more paper clips before collapsing than the flat bridge with no support.
Build a Bridge STEM Challenge Worksheet
More bridge building ideas for kids
Teach Beside Me has a brilliant popsicle stick bridge.
Experiment with different types of paper bridges.
Build and test an eggshell bridge. It might be stronger than you think!