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Built on a collection of 40,000+ popular, high-quality books from 250+ of the world's best publishers, Epic safely fuels curiosity and reading confidence for kids 12 and under.

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online access fun thousands children great kids ebooks books

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Built on a collection of 40,000+ popular, high-quality books from 250+ of the world's best publishers, Epic safely fuels curiosity and reading confidence for kids 12 and under. Get Started

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BrainPOP Jr. - Animated Educational Site for Kids - Science, Social Studies, English, Math, Arts & Music, Health, and Technology

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Today's Wonder of the Day was inspired by Faith. Faith Wonders, " how did the person who made the first clock know what time it was " Thanks for WONDERing with us, Faith!

As you make your way through a school day, you're probably very aware of what time it is. School probably starts around 8 or 9am. You probably know exactly what time and lunch occur. You're probably also aware that school gets out around 2:30 or 3:30pm. How do you keep track of all these different times?

Fortunately , thanks to modern technology, there's no of timekeeping devices you can rely upon. At home, you probably have at least one on the wall. You may also have appliances, such as a microwave or an , that have clocks.

Some kids wear a wristwatch to keep track of the time throughout the day. In lieu of a wristwatch, other kids might rely upon a smartphone instead. At school, every classroom likely has a on the wall.

Have you ever WONDERed, though, what people did before modern clocks were invented? How did they know what time it was? How did they keep track of appointments? How did they know when they needed to be somewhere?

Although we can't know for certain how the earliest human beings kept track of the time, scientists believe they probably relied upon the world around them. For example, historically, humans have relied upon the movement of the Sun across the sky to track time.

Historians believe many ancient peoples, including the ancient Babylonians, Egyptians, Chinese, and Hindus, divided the Sun's into different timekeeping periods. The ancient Egyptians, for example, built tall that would shadows to help divide the day into sections.

These worked in much the same way as sundials, which were a popular of timekeeping long ago. Of course, sundials didn't help much at night or on cloudy days. To help keep time when it wasn't sunny, ancient peoples also learned to track the movement of the planets and constellations after dark.

Other devices were developed over time, including hourglasses and water clocks. These devices relied upon the time it would take a particular substance, such as sand or water, to move from one part of a container to another. Rather than clocks, though, these devices were more like timers.

How did people long ago set up a meeting at a certain time in the future? Some historians believe many people relied upon a technique as simple as pointing to an area of the sky. When the Sun reached that point, that's when you would meet the next day.

Of course, humans, being the clever creatures we are, relied upon a variety of solutions to the problem of timekeeping. For example, many people simply trained their bodies to wake up at the first light of dawn. Others may have relied upon animals, such as roosters, as alarm clocks.

If people had to be up before dawn, they might have relied upon the full bladder method. By drinking a lot of water before going to bed, they would be assured of waking up in the middle of the night to go to the bathroom!

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Today's Wonder of the Day was inspired by Faith. Faith Wonders, " how did the person who made the first clock know what time it was " Thanks for WONDERing with us, Faith! As you make your way through a school day, you're probably very aware of what time it is.

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Read Measuring Time: The Calendar on Epic

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Read Measuring Time: The Calendar on Epic

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Instantly access Measuring Time: The Calendar plus over 40,000 of the best books & videos for kids.

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Evolution of Time-keeping Devices in 3 minutes

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Who decided a year should have 12 months? Curious Questions & Answers | Educational Videos by Mocomi