Ages 4-7 · child and adult
String telephone: a secret message
Connect two paper cups with string and try sending a quiet message.
Set your own pace. Preparation depends on your materials.
What to gather
- Two paper cups
- About 2 metres of cotton string
- Tape and an adult-only hole-making tool
Keeping it safe An adult stays throughout. Never wrap string around the body or stretch it across a walkway. Put it away after play.
Choose a challenge level
Ages 4-5
Use short messages such as an animal or colour. The adult helps keep the string taut.Ages 6-7
For a third trial, lightly touch the taut string. Does the sound change? Keep voice and distance the same.Step-by-step instructions
An adult makes a small hole in the centre of each cup base. Thread each string end from outside to inside.
Tie a large knot inside each cup so it cannot slip through. Reinforce around the holes with tape if needed.
Stand facing each other and gently pull the string taut. One player speaks softly into a cup while the other listens. Let the string slacken and compare.
TATAAA
Now turn it into a game
Agent password: send two words, such as blue bear. The listener repeats and draws them. Swap roles; never shout into the cup.
When it gets tricky
No sound? Keep the string off furniture and check that the holes are not torn. Try in a quiet room.
When an experiment goes wrongWhen you are done
The listener repeats a quiet message and you try taut and slack string.
If your child does not want to continue, it is fine to stop. You can safely swap roles or adapt the rules.
What to notice
Your voice vibrates the cup base. The taut string carries vibrations to the other cup, which produces sound.
Background reading
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