String Telephone Science Experiment

When we speak, our vocal cords make molecules in the air vibrate. Ask the children to hum a song while holding their hands against their throats to feel the vibration. Vibration is what creates sound waves.

When you speak into a cup, your voice vibrates the air inside the cup, which in turn vibrates the bottom of the cup. These vibrations travel along the string and then vibrate the cup on the other end. The vibrations are converted to sound waves, so the person can hear through the other cup.

You will find that keeping the line taut is the key to making the string telephone experiment work. When the string is slack, the vibrations dissipate along the way, and they never reach the cup on the other end.

Another tip is to make sure the string doesn’t touch anything along the way. Otherwise, the sound waves will travel the wrong way.

You can use the DIY string telephone to hear surprisingly far!

Here are a few experiments to try:

Use a plastic cup instead of a paper cup or vice versa. Does the type of cup matter?

Use different types of strings and observe how the strings change the quality of sound. You can try wool, cotton twine, fishing line, kite string, etc.

Try different string lengths. How long can you make the line and still hear each other?

Try making the string slack. Can you still hear anything?

Touch the string to an object. Can you still hear anything?

Practice sending messages back and forth and see how clearly you can hear.

Use our String Telephone experiment recording sheet to record findings.

• Selection of disposable cups. (Plastic, paper, different sizes)
• Selection of different string, wool, fishing line, thread etc
• Paperclips
• Scissors
• String Telephone experiment recording sheet

Ducans Reply Letter

Vocabulary:

Duncan needs to write a reply to his crayons. Children can choose a colour to reply to thinking carefully about the crayons' needs and wants.

Think about the format of the letter, is it a formal or informal reply. Does the crayons address need to be included? How should Duncan sign off the letter? What tone of communication is being used?

The letter can include illustrations to support the reply. During SCARF reflection time, encourage children to read and share their reply letters with each other.

You will need:

• Paper and pen

Best Colour Debate

Invite children to select the colour they think is the best.

Why is this colour the best/ most important?

Ask the children to write a short speech to explain to their classmates why their colour is the best.

Once all children have communicated their views, class teachers can conduct a blind vote using a tally chart and inviting children to come to their desk and score one at a time. (They cannot vote for their own colour.)

Reveal the results of the ‘Best Colour’.

Refer to ‘Democratic vote’ - organised in a fair way in which everyone has the right to join in making decisions and have their opinions heard.

You will need:

• Paper and pen