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In those parts of the world where some months of the year are very cold, mice and other small mammals hibernate. This means that they go into an inactive, sleep-like state for the cold period and only fully wake up when the weather turns warm again. Hibernating animals breathe much more slowly and their body temperature falls.  They also need much less food.  They build up a thick layer of fat during the warmer months and use it up very slowly during hibernation. A dormouse can sleep in its nest for up to nine months in a year. It may wake up at intervals during this time to nibble at its store of nuts and berries. Read more:  Why do bats hang upside down? Do Bats Hibernate In The Winter? Not all bats hibernate, but only those living in places where during the winter months the insect prey becomes scarce, so the bats can’t support an active metabolism. During hibernation, bats wake up every couple weeks, when they may move around and even fly short distances....

1.You need: 2.Find out more about a dinosaurs. Research Magazines Books Internet Museums 3.Draw its body, tail, legs, neck, and head on a sheet of card. 4.Colour and cut out the parts. 5.On the back of each part write a sentence about your dinosaur. 6.Put your dinosaur together. 7.Tell your class about your dinosaur.

1.You need: 2.Make a hole in one end of the box. Cut two slits in each side. 3.Draw round the end of the box. Cut out the square. Colour a computer game scene on the paper. 4 Glue the scene to the back of the box. 5.Draw your game characters on the end of the strips of card. Cut the card out around the drawings. 6.Put your characters in the slits. Look through the hole in the end of the box. 7.Explain your game to your class.

Home Soil Test: You will need: a handful of garden soil or forest floor soil water a small stick a small glass jar 1. Half fill a glass jar with water and then put in a handful of soil. 2. Use the stick to stir the soil into the water. Then leave it to settle. 3. Watch as the soil settles in different layers. What falls to the bottom of the jar first? What settles above that? And what settles as the top layer? Even if you wait a long time, the water will never become completely clear because some of the smallest pieces of clay will remain floating in it. Bits of plants and leaves will stay floating on the surface. Try this experiment with soil from different places. Are the different layers in the jar always the same thickness? Soil composition - What is soil?  Almost all the land on our planet is covered by a layer of soil. Do you know what's in the soil? Soil is a mixture of living and non-living material. It includes the rotting remains of plants and ani...

Animals feed on other animals or plants or both. But some small animals actually live on, or even in, the animals or plants from which they feed. They eat small amounts of the living bodies of larger animals or plants, which also provide shelter for them. Animals that do this are called parasites.  Some plants are parasites, too. They grow on other plants and feed from them. They don't make food for themselves as other plants do. The animal or plant that parasites live on is called the host. Animal parasites Some animal parasites feed by sucking the blood of larger animals. These blood-suckers include ticks, fleas, lice, and leeches. One of these parasites clings to the body of the host animal and bites into its skin. The parasite's body becomes swollen as it fills with blood. Fleas jump from one part of the host animal to another, sucking its blood. Fleas live in clothes and on the bodies of humans, birds, and other animals. They suck the blood of a host anima...

A hurricane is a powerful, whirling storm that starts over tropical oceans.  Hurricanes can also be called typhoons or cyclones. How do Hurricanes Form? In tropical regions, warm air rises quickly above the sea. It contains large amounts of water vapor that has evaporated from the sea below. Above the sea, the water vapor cools, turns back into water droplets and forms storm clouds. Sometimes, the very moist air traveling upwards meets strong winds that pull it up even higher. More moist air then rises from above the sea, making a huge, swirling ring of wind and rain. Hurricane winds rotate at speeds of up to 150 miles (240 kilometers) an hour around a calm area in the center, called the eye of the storm. The hurricane may last several days, moving forwards at about 12 miles (20 kilometers) an hour. Most of the damage caused by hurricanes happens because the storm creates huge waves that flood the land. This kind of storm needs a constant supply of moist air risin...

What is a tornado? The weather can sometimes be very dangerous. Violent storms can create fierce, twisting winds that seriously damage anything that gets in their way. A tornado is a powerful, twisting windstorm.  What Causes a Tornado to Form? Most tornadoes develop along a boundary, called a front, where cool, dry air meets warm, humid air. Large thunderclouds appear, thunder begins to rumble, and a nearby cloud becomes dark and dense. If the warm air rises very quickly, more warm air rushes in to replace it. As this air rises, it sometimes starts to rotate. The rotating air forms a tornado, or twister, which is shaped like a long, thin funnel stretching down from the cloud towards the ground. If this funnel meets the ground, it sucks things up like an enormous vacuum cleaner, making a swirling mass of dust and dirt, destroying almost everything in its path. Tornadoes sometimes make houses explode! When the tornado sucks up air from around the outside of the h...

Lightning is a giant spark of electricity in the sky.  During a storm, strong winds blow the tiny particles of dust and water around inside the cloud and make them collide with one another. Normally, each particle in the cloud has what scientists call a positive and a negative electrical charge. But when the particles collide with each other, these charges separate. Most of the positively charged particles move to the top of the clod and most of the negatively charged particles move to the bottom. What Causes Lightning? The spark happens when the negative charges in a thundercloud meet the positive charges in another cloud, or on the ground. Lightning strikes somewhere on the earth about 100 times every second!

What is a Bacteria? Bacteria are very small living things that have only one cell. Some scientists classify bacteria as plants, because some kinds of bacteria can make their own food from sunlight, like green plants do. But there are many differences between plants and bacteria. So many scientists say that bacteria belong to a separate kingdom of living things, which is called the monera kingdom. There are thousands of different kinds of bacteria.  Each bacterium is so small that you need a powerful microscope to see it. These rod-shaped bacteria are on the head of a pin. The photograph is enlarged so much that the surface of the pin looks rough, not smooth. Many kinds of bacteria are useful.  They help living things to survive and be healthy.  Some of the bacteria on your skin protect you from other tiny living things that might harm you. Those in your intestines help to break down the waste products that your body eliminates. They even help to make vita...

Despite their dramatic behavior, thunderstorms are the smallest of the different kinds of storms. They average around 16 km (10 mi) across, but they often occur in lines that can be a few hundred miles long or clusters a couple hundred miles across. Thunderstorms are often part of larger storms such as hurricanes. While thunderstorms occur most commonly in warm weather, they can happen in the winter. Sometimes snow will fall from a thunderstorm instead of rain; this is called a “thunder snow.” Every thunderstorm includes lightning because lightning causes thunder. Lightning creates a danger in any thunderstorm, no matter how large or small. Many thunderstorms drench the countryside with heavy rain, so you also have to worry about flash floods—that is, floods that rise very quickly, sometimes running over the banks of normally small streams. If a thunderstorm is strong enough, it can also create hail, or balls of ice that fall from the storm. Hailstones are usually less t...

Water is not only the most common substance on earth, it is also one of the most unusual. No other substance can change its shape and form like water can. Water is made up of tiny particles called molecules.  A single drop of water contains millions of molecules. Each of these molecules is made up of even smaller particles. These are called atoms. Each water molecule contains atoms of two substances, hydrogen and oxygen. Two atoms of hydrogen join with one atom of oxygen to form water.  Scientists give hydrogen the symbol H and oxygen O. These symbols are used together to give the scientific name for water—H20. Can you see why? Water can exist in three states—a solid, a liquid or a gas.  The molecules that make up liquid water are always moving freely. When water is cold, the molecules slow down. If cooled enough, water can change to ice. When rain water is frozen, it takes on other forms, such as snow, hail, or sleet. When water is heated to a boili...

What is the recommended daily water intake? Without enough water, the human body is soon unable to go on working.  Our blood is mostly made of water. Blood carries oxygen from our lungs and nutrients from our intestines to all parts of our bodies. Nutrients are the useful chemicals that we take from our food. Water also helps to keep our muscles and joints running smoothly. Some of this water is lost because we breathe it out. In cold weather, we can see the water vapor condensing in the cold air as it comes out of our mouths. We lose water when we perspire and when we go to the toilet. If we are ill, we often have a fever and perspire more than usual.  This is why, if we are ill, the doctor may tell us to drink plenty of liquids. Did you know that you could live without water for only about a week?   You probably think your body feels firm and solid because it's full of strong bone and muscle. But, in fact, about 65 per cent of your body is made up of wa...

Did you know that nearly three-quarters of the surface of the earth is covered with water?  There are vast oceans like the Atlantic and the Pacific, and smaller seas like the South China Sea and the Red Sea. There are lakes, rivers and streams. Around the North and South poles, frozen water forms icecaps that last all the year round. Below ground, there is even more water.  This has soaked down through the soil to fill the spaces between the rocks with large stores of water. There is even water in the air.  Clouds are made up of millions of tiny droplets of water. Clear skies contain moisture which moves around in the air as an invisible gas. Water is different from every other substance on earth because it can be found in its natural state in three different forms. When we speak of water, we usually mean water as a liquid.  When water is solid, we call it ice.  When it is a gas, we call it water vapor. Water can change very easily from one...

Do Bats Hibernate? Not all bats hibernate, but only those living in places where during the winter months the insect prey becomes scarce, so the bats can’t support an active metabolism. During hibernation, bats wake up every couple weeks, when they may move around and even fly short distances.  What Is Hibernation? In those parts of the world where some months of the year are very cold, mice and other small mammals hibernate. This means that they go into an inactive, sleep-like state for the cold period and only fully wake up when the weather turns warm again. Hibernating animals breathe much more slowly and their body temperature falls.  They also need much less food.  They build up a thick layer of fat during the warmer months and use it up very slowly during hibernation. A dormouse can sleep in its nest for up to nine months in a year. It may wake up at intervals during this time to nibble at its store of nuts and berries. Read more:  Why do bats...

What Was The Pony Express? If you receive a message and pass it on to someone else, you are acting as a relay. Relays are useful for sending messages over long distances. In telecommunications, relays pick up a signal and make it stronger before passing it on. Without relays, the signal would be too weak to understand by the time it reached the end of its journey. One of the most famous relay systems was the Pony Express , which carried mail from St Joseph, Missouri, in the United States of America, over the mountains to Sacramento, California . This was in 1860 and 1861, before there were railways or telegraph lines across North America. Pony Express riders used fast horses or ponies.  The horses were changed every 10-15 miles (16-24 kilometers). Each rider traveled 74 miles (120 kilometers) or more in a working day. So a message got through much more quickly than it would have with a single messenger. But by October 1861, the transcontinental telegraph was completed,...

Human body is like a wonderful machine, in which each part has a special job to do. But in order for each part to work properly and in harmony with all the other parts, we must take care of our body. To stay healthy, you need to eat meals that contain a balanced choice of foods. You need to take some kind of exercise regularly. And you must also rest, to allow your body to regain energy. It is important that you wash and keep yourself clean, to reduce the chances of catching a disease or an infection. Eating the right foods Many people are lucky enough to be able to eat all the right foods they need to keep alive and healthy. While you are growing, you need plenty of protein. This is found in foods such as fish, meat, milk, eggs, beans, and nuts. You also need to eat fresh fruit and vegetables. You should eat regular meals and not go for long periods of time without eating. Taking regular exercise As well as eating the right foods, you must keep your muscles and joints healthy...