Innholdsfortegnelse for November/December 2019 i Click Science and Discovery Magazine for Preschoolers and Young Children

You want to talk to Grandma, but Mom says it’s too early to call. Grandma is probably still asleep. But you’ve already had breakfast, so why hasn’t Grandma? Mom says it’s because Grandma lives in a different time zone. What does that mean? Earth is round. It spins like a top as it moves around the sun, so sunlight hits different parts at different times. When it’s day at your house, it’s night on the other side of the world. So different places have different time zones. If there were only one time zone, every clock would say the same time, even though it was morning in some places and afternoon or night in others. Time zones divide the world into sections that match where the sun is in the…

How old are you? Can you find your birthday on a calendar? Long, long ago, people had no calendars. To keep track of time, they watched the sky and the seasons. They saw the sun rise each morning and set each night, and they called the length of time from one sunrise to the next a day. They watched how the moon changed from night to night. It grew from a thin crescent to a fat circle, then shrank back down and grew again. They used moon time, the 29 or 30 days between one new moon and the next, to describe other lengths of time. They saw that spring, summer, fall, and winter followed one another in a regular pattern, a pattern that could be used to measure longer…

Animals don’t have clocks, but they still need to know the time. Especially when it’s time for winter. They can tell winter is coming by the amount of daylight. Summer has long days. Winter days are short. When the days start to grow shorter and the nights longer, winter is on the way. What do the animals do then? Time to Move Many animals migrate. They move to places where the weather is better. Birds often fly long distances when they migrate. Some hummingbirds fly without stopping for almost a day and travel hundreds of miles. Monarch butterflies also fly far to migrate. Every year millions fly from the United States all the way to Mexico. They spend the winter in warm Mexican mountains. Ocean animals migrate by swimming to…

The hourglass, or sand clock, has been used for hundreds of years to keep track of time. You can make one. What you need • 2 clean, dry, clear bottles the same size • strong tape • salt What you do 1. Fill one of the bottles almost to the top with dry salt. 2. Cover the top tightly with a piece of tape. Poke a small hole in the tape with the tip of a pencil. Test the hole to see if the salt flows out easily. Change the hole size if you need to. 3. Put the empty bottle on top of the salt bottle, and firmly tape them together. 4. Turn your salt clock over. Watch the second hand on a clock to see how long it…

Many years ago in China, a young boy named Chuan and his friend Jing Jing traveled to the city of the emperor with Ying-Fa, a powerful warlord. The emperor had invited all the warlords in the country to a feast, and Ying-Fa was eager to arrive before the others in order to gain the emperor’s favor. “Time passes slowly,” Chuan grumbled as they marched. “Each day passes in the time it takes for my leather water bag to empty,” said Jing Jing. “I fill it every morning and it leaks out through this tiny hole by nightfall.” She wrung moisture from the bottom of her coat and made a face. After some days they noticed more people on the road. A rival warlord mounted on a fierce horse nodded at…