Object: a stopwatch

Good morning (or evening), boys and girls. Some of you might be getting watches or clocks for Christmas. What do we use watches for? (Let them respond.) Watches help us to tell time, of course. We know what time to get up, to eat, to go to work or school, and what time to go to bed. A regular watch or clock will help you with all that. But the watch I brought today does just the opposite. It stops time. It's called a stopwatch. Some of you have seen these before. People who run races use these kinds of watches to tell them how fast they run. The time keeper pushes this button when the runner starts and then when the runner stops, the time k…