What children will learn
- Explore how shape affects strength (folds, tubes, arches)
- Test, record and improve a design
- Count and compare results
You'll need
- 5 sheets of A4 paper
- Sticky tape
- Two books of the same height
- Coins or small washers
- A ruler
How to do it
- Place two books 20 cm apart. The bridge must span the gap.
- Test a flat sheet of paper first. How many coins does it hold before collapsing? (Usually very few!)
- Now design a stronger bridge — try folding the paper into a zig-zag, rolling tubes, or making an arch.
- Add coins one at a time to the middle of the bridge and record how many it holds.
- Improve your best design and test again. Which shape was strongest, and why?
Make it easier
Shorten the gap to 10 cm and use fewer coins.
Make it harder
Limit materials to 2 sheets and 30 cm of tape, or calculate the strength-to-weight ratio.
Parent tip: Ask ‘why do you think that one worked?’ — explaining their thinking is a great science skill.
Fantastic work! Every little step helps you grow.