Things You'll Need
Instructions
Remove one end completely from each of two tin cans, and leave one end intact. The end that has been removed will be the phone's "receiver," and the intact end will hold the phone's "wire."
Turn one can upside-down, so that its intact end is facing up.
Drive a nail through the center of the intact end using a hammer. The nail should make a neat hole in the end of the can. Repeat with the other can.
Thread one end of the string through one of the nail holes. Make a knot in the string on the inside of the can, so that the string remains attached to the can. Repeat with the other can and the other end of string. The tin cans should now be tied to either end of the string.
Hold one tin can, and give the other tin can to someone else. Walk away from each other until the string between the cans is taut.
Speak into the open end of one tin can while your partner listens to the open end of her tin can. Switch roles, and listen to the open end of your tin can while your partner speaks into the open end of his.