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Cardboard Climb

A sticky way to reach the top

Australian Curriculum links

  • Science > Physical Sciences > Year 4 > ACSSU076

You’ll need

  • Thick cardboard (cardboard from moving boxes works well)
  • Plastic drinking straw
  • 2m length of string
  • Scissors
  • Tape
  • Pen, or pin and pinboard
  • Coloured pencils and decorations

Try this

  1. Draw and cut out an animal on cardboard.
  2. On the back attach two short lengths (5cm) of straw angled slightly inwards at the top (like a capital letter A, but with a gap between the straws at the top).
  3. Thread a long length of string through one straw from the bottom to the top, and back down the other straw from the top to the bottom. Both ends of the string should be hanging downwards, with a loop of string at the top of the animal.
  4. Place the loop in the string around a pen or pin in a board and slide your animal to the bottom of the string (away from the loop). If using a pen, ask a friend to hold it in the air.
  5. Gently pull down alternatively on either string to make your cut-out move upwards.

Investigate further

  • Does nylon string work as well as other types of string?
  • Is the length of the straw or the angle of the straws important?
  • Try adding other moving parts. Will it still work if the climber has jointed limbs?
  • Will it work along the floor? Or only moving upwards?

What’s happening?

When the string is pulled on one side, it moves freely through the straw, allowing the climber to move up. However, the angle of the second straw creates friction and stops the character from moving on that side. Alternating between pulling the string on each side enables the cardboard to creep forward along the string.