Learning to read analog clocks is harder for modern kids than it was a generation or two ago when kids actually saw analog clocks around. This means that we can sometimes get so focused on this one skill that we don’t get into the concept of time itself. And yet the idea of what time is and how and why we measure it is worth studying.
Start with an hourglass or minute timer using sand. You can get a very safe and sturdy that will ensure that your classroom doesn’t get sandy, or you can boldly allow your students to make one themselves with a couple of water bottles.
If you decide to go the homemade route, make your life easier by using a Tornado Tube instead of duct tape to connect the two bottles. Remove the rings from the mouths of the bottles, carefully insert the sand into one bottle, attach the second bottle to the first securely, and you have a sand timer. Sort of.
When making a sand timer in the classroom, the most essential point is figuring out how to use it to tell time. In order to do this, you have to measure your sand very carefully, and then measure the length of time it takes for the sand to pass from one bottle to the other, and then calculate how much sand you’d need for the length of time you want your sand timer to tell. Then you have to test it. I don’t tell students this ahead of time. I like them to discover it on their own, in hopes of their understanding and remembering something about the scientific method and the importance of controlling variables. It depends how much of a hurry you’re in.
Certainly, you can just say that whatever the length of time your timer happens to measure when you finish throwing some sand in, is the unit of time. If the timer takes 22.75 minutes to empty sand from one side to the other, then it’s a 22.75 minute glass rather than an hourglass. Or you can make up a name for the period of time in question and say that 22.75 minutes = 1 gloomph, and let it be a gloomphglass. Brainstorm with students the advantages and disadvantages to this approach.
Then try using your sand timer, whether ready-made or classroom-made, to measure time. Use it to time tests, games, breaks, and such. Compare it with stop watches, clocks, and kitchen timers and list the advantages of disadvantages of each.
Other types of clocks
Once you’ve gone through this process, you’ll be ready to think of other ways to measure time. For example, you could make a candle clock by timing the distance your candle burns in one minute and then marking off 1-minute increments. You can then burn the candle to measure minutes. Fire clocks of various kinds were used in Asia and Europe into the 20th century.
Water clocks were also popular. The other name for a water clock is “clepsydra.” They were used in ancient Egypt, and have probably been around since before the 15th century BC. You can make one by setting a paper cup on top of a jar. Put a hole in the bottom of the cup and fill it with water. Time the flow of water into the jar and mark the outside of the jar at intervals to show the passage of time. When the jar is full, just pour the water out and use it again.
If you’ve tried sandtimers and fire clocks, then your class should be ready to realize that one of the big issues in creating a water clock would be making sure that the water flowed at a steady rate.
In fact, you can make a clock of anything that takes place at a steady rate, from the movement of the earth (as with sundials) to an electric motor turning the hands of a modern analog clock. If you’d like to indulge in a little irony, you can make a quartz clock out of old hardrives, following the directions from instructables.com at that link.
- ThoughtCo offers a history of timekeeping.
- Teaching the kids to code? Why not? Here’s a tutorial for building a clock in Visual Studio Basic.
- A very clear video tutorial on how to make a water gun alarm clock. You may not be soldering circuit boards in class; if not, you can still use this to practice note-taking and sequencing, or as a writing prompt to inspire your students to think of their own innovative clock-building ideas.
- The National Institute of Standards and Technology has a Walk Through Time that’s full of intriguing tidbits for your classroom timeline.
- The National Watch and Clock Museum has a glossary page with all the special timekeeping terms.
- Cinderella gives some awesome opportunities to connect clocks with reading.