Does your little one pretend to talk on the phone with you?  We have a few pretend phones the children play with, and it’s quite funny to hear their conversation.  They greet and say good-bye in the same manner as I do too, which I find pretty amusing.

We had more fun with the idea of “calling” each other and made the classic paper cup string phone.  Who knew two paper cups and a long piece of string could be so much fun?!  We had a blast!

Here’s what you need:

  • 2 paper cups
  • Scissors or a sharp pencil
  • String


  1. Poke a hole with your scissors or sharp pencil in the center of the bottom of both cups.
  2. Cut the string; it should be at least 3 feet long.
  3. Thread the end of the string through the cup from the outside and tie a knot bigger than the hole, so that it will not pull through the cup.
  4. Do the same for the other cup.
  5. Now you can use the cups to listen and talk into!  Make sure that the string is taut between the two people using the “phone.”

Science Kids explains how this works:   Speaking into the cup creates sound waves which are converted into vibrations at the bottom of the cup. The vibrations travel along the string and are converted back into sound waves at the other end so your friend can hear what you said. Sound travels through the air but it travels even better through solids such as your cup and string, allowing you to hear sounds that might be too far away when traveling through the air.


Paper Cup String Phone

The boys had tons of fun “calling” each other.



Paper Cup String Phone

I had so much fun taking my call!

Paper Cup String Phone

Our string (we used yarn) was about 6 feet long!

Hope you’ll give your little one a ring with this fun science activity!

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