Learning about Sound and the telephone

We have been learning about the invention of the telephone.  Starting with learning about Alexander Graham Bell was and how he invented the telephone.  We then looked at how the telephone has changed since the original Alexander Graham Bell phone to the latest smartphone.

We then decided to make our own phones using cups (plastic and paper) and string.  Once made, we tested them to see if they would work.  We were delighted with the results, but learned we need to keep the string very taut, for them to work well and for the vibrations to travel down the string.