Object:
An hourglass (a small kitchen timer or one from a game is
perhaps most readily available)
Good morning! Before people had clocks to keep time, they used
what is called an "hourglass." It looked very much like this --
which is a smaller version of an hourglass. The sand runs from
the top to the bottom. How long do you suppose it takes all the
sand in a true hourglass to get to the bottom? (Let them answer.)
It would take an hour! That is why it was called an "hourglass."
Sometimes today people use a smaller version like this one
which takes only three minutes to run from one side to the other.
