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Your eyes are like two tiny movie cameras inside your head. They are sending a steady stream of pictures back to your brain, like a television camera sending live pictures back to a TV screen. Your eyes have a part called the lens, just like a camera. The lens helps to bring everything you look at into focus, so that details are as clear as possible. What are Rods and Cones? Human beings are luckier than many other animals because they see in color. Some other animals, such as birds and butterflies, can also see colors. To see colors, we have special cells in the eye called cones.  They share the work of seeing with other cells called rods. Rods do not detect the difference between colors and don’t need as much light as cones to make them work. So at times, rods are more useful to you than cones, such as at night when the light is very dim. Have you ever been for a walk in the moonlight and noticed how pale, silvery, and colorless everything seems? Photographers can tak...

Your ears are organs. They aren’t just the flaps of skin you can see! Your ears stretch deep into the skull. They do a very important job. They collect sound waves, which are tiny vibrations of air, and change them into signals that your brain can understand. To do the difficult job of hearing, the ear has three different parts. These are called the outer ear, the middle ear, and the inner ear. What does the Outer Ear Do? The outer ear consists of the ear flap, which is the part you can see, and a hollow tube, called the ear canal. This leads to the eardrum. The eardrum is made of a sheet of skinlike material called a membrane. This vibrates when sound waves travel down the ear canal. What does the Middle Ear Do? The middle ear is like a hollow cave. It contains three bones, called the hammer, the anvil, and the stirrup.  When the eardrum vibrates, it makes the hammer vibrate. This movement is passed on to the anvil and then to the stirrup. The stirrup makes anot...

Sense organs are specially developed parts of your body. For example, each of your eyes has a retina for detecting light. And each of your ears has a cochlea for detecting sounds. Can you name the “five senses”?  Try to name them before reading further. These senses send information to the brain. There are special parts in the brain that sort out this information. It is then passed to other parts of the brain, which can compare information from different sense organs. Your brain then signals what you are: seeing,  hearing,  smelling,  tasting, and  touching.  These five senses allow you to know what is in your physical environment. What are the Five Senses? The hidden senses Another set of senses, of which you are unaware of most of the time, helps control your inner organs.  These senses control the timing and movement of food through your body. They measure the amount of sugar and salt in your blood. They regulate the amount...

What do Kidneys do? Your kidneys make the waste liquid your body has to get rid of. You have two kidneys, one on each side of your spine, behind your stomach. They are shaped like beans and are nearly as large as your heart. Your kidneys filter your blood as it travels through them. Kidneys take out waste products that your blood has carried away from all the cells. One of the main waste products is called urea. This is made after your cells have broken down substances called proteins.  Kidneys also take away some salt and water from your blood if it contains too much of them. Your body must keep a balance of salt and water. Keeping this balance is the responsibility of the kidneys. Your kidneys then get rid of the water and waste products by making droplets of a liquid called urine.  The urine passes into your bladder through two tubes called ureters.  Your bladder is a bag made of muscle, which stretches as it fills with urine. When you decide it’s time t...

What is digestion? When you eat, your food begins a long journey through your body. Most of your food is broken down into lots of tiny, simple pieces so that your body can use it. This breaking- down process starts in your mouth and is called digestion.  The various substances that aid in digestion are known as digestive juices. Your body uses food to acquire energy. Food contains special chemicals that provide energy in your body’s cells. Energy keeps all the different parts of your body working. Without energy, all your muscles and every other part of you would stop working. Food also helps your body grow and repair parts that have become worn out or damaged. Food to keep you healthy Food contains many different substances that work together to keep you going. Food substances that give you energy are called carbohydrates and fats. Carbohydrates are found in foods like potatoes, rice, and bread. Milk, butter, and cheese are fatty foods. The parts of your food that h...

Your blood has lots of different jobs to do as it travels around your body.  It carries the oxygen you have breathed in to every single cell. It also carries food and other substances that your cells need. When the cells have done their job, they make waste products which your blood carries away. What is blood made of ? Like other parts of your body, your blood is made from cells. There are two main kinds of blood cells—red and white.  The red blood cells are the ones that contain a red substance called hemoglobin. It is the hemoglobin in the red blood cells that carries oxygen from the lungs. The white blood cells kill germs that enter your body. There are fewer white cells than red cells. A liquid called plasma surrounds the blood cells.  This is made mostly of water. The plasma carries food to the cells and carries waste products away. Blood vessels - The tubes that carry blood Blood travels through tubes called blood vessels.  The vessels that c...

How do we breathe? As you breathe, your chest moves in and out, and up and down. Inside your chest, there are two flexible, sponge like organs on either side of your heart. These are your lungs.  When we inhale (take in air), we breathe in oxygen, a gas which helps to give us energy. When we exhale (expel air), we breathe out carbon dioxide, a harmful waste gas. When you breathe in, your lungs fill with air and become larger. When you breathe out, your lungs become smaller as gas is squeezed out of them. Breathing in You inhale air through your nose and mouth. Inside your nose are tiny hairs that catch dust from the air. There is also a sticky liquid called mucus that warms and moistens the incoming air and catches many of the germs you breathe in. The air you breathe in goes down a pipe called the trachea, also known as your windpipe. From your windpipe, air enters each lung through two tubes called bronchi.  Each bronchus divides into smaller and sm...

The human body has 639 muscles. Not all are joined to your bones. For example, muscles line your blood vessels to keep blood flowing. Your lungs work because of regular muscle movement. Muscles in the Human Body Some muscles move only when you decide to stand up, sit down, or move in other ways. These are the voluntary muscles that are joined to your bones. There are other muscles that work without your thinking about them. These involuntary muscles are made of smooth muscle fibers. They mash the food material in your stomach and then act to move it along through your intestines. Your heart is made of another special kind of muscle called cardiac muscle . It moves in a regular rhythm as it pumps blood to all parts of your body. How do muscles work? Muscles are made of tough, elastic tissue. They are built so that they can contract, which means that they become shorter. When the muscles whose ends are joined to bones contract, they pull at the bones and make them mo...

The human body has 639 muscles. Not all are joined to your bones. For example, muscles line your blood vessels to keep blood flowing. Your lungs work because of regular muscle movement. Some muscles move only when you decide to stand up, sit down, or move in other ways. These are the voluntary muscles that are joined to your bones.  There are other muscles that work without your thinking about them. These involuntary muscles are made of smooth muscle fibers. They mash the food material in your stomach and then act to move it along through your intestines. Your heart is made of another special kind of muscle called cardiac muscle. It moves in a regular rhythm as it pumps blood to all parts of your body. Muscles In The Human Body How do muscles work? Muscles are made of tough, elastic tissue. They are built so that they can contract, which means that they become shorter. When the muscles whose ends are joined to bones contract, they pull at the bones and make them...

Human body moves in many different ways. You can bend, stretch, turn, and twist. You can move because your bones move at your joints, places where your bones meet. But your bones can’t move by themselves—they need something to pull at them.  This job is done by your muscles, which are joined to your bones in order to move them. There are many joints that help your body move. When you turn your head, bend your knees, or twist your wrists, your joints are in action. Some joints, such as those in your skull, do not move. These are called fixed joints. Each of the other kinds of joints does a specific type of movement. Types of joints in the human body Types of joints in the human body - Ball and socket joints give you the most movement. The round end of one bone fits into a hollow part of another bone. Examples are your hip joints and shoulder joints. - Hinge joints work like a door on a hinge. Movement in hinge joints is only in two directions. Your knees an...

Humans have about 200 bones in the body, which are joined together and make up the skeleton. Your skeleton helps give your body its shape. The bones of your skull determine the shape of your head. Long bones hold muscles that shape your arms and legs. Rib bones curve to make the sides of your chest. Your skeleton is the framework of your body. It holds you up and also helps you to move around. Some bones protect your main inner organs. For example, your skull protects your brain. And your ribs make a rib cage around your heart and lungs. What are bones made of? Bones are hard tissues that are living parts of your body, just as your brain and heart are living parts. Bones contain cells that divide and multiply, causing you to grow. These cells are also always rebuilding the bony tissue to keep it strong. Rebuilding happens less as people grow older. So a broken bone will often heal much more quickly in a child than in an adult. Bones store substances called minerals, which your bo...

Bones are hard tissues that are living parts of your body, just as your brain and heart are living parts. Bones contain cells that divide and multiply, causing you to grow. These cells are also always rebuilding the bony tissue to keep it strong. Rebuilding happens less as people grow older. So a broken bone will often heal much more quickly in a child than in an adult. Bones store substances called minerals, which your body uses. Calcium is a mineral. It helps to make the bones hard. Bones have a strong covering, called periosteum. Inside, there is a hard layer of compact bone. A long bone, such as the thigh bone, has spongy tissue at its ends, called cancellous bone, and soft marrow in its hollow center. Some parts of your skeleton, such as your arms and legs, have only a few long bones. Other parts, such as your hands and feet, have many small bones. How are bones held together? Your bones are held together by strong, flexible straps called ligaments. The ends of the b...

Most of the vertebrates that live in the ocean are fish. Some mammals, reptiles, and birds live there, too. There is only one group of vertebrates not found in salt water. These are the amphibians. Fish have always lived in the sea, of course. There are more than 13,000 different kinds, or species, living in the sea. But the mammals found in the sea are descended from land animals.  They have to come to the surface to breathe, because they have lungs, not gills. Fish in the ocean Fish come in all sorts of different shapes and sizes.  Some are flat so that they can lie on the seabed without being seen.  Eels have snakelike bodies.  Rays, like the skate, are kite-shaped and seem to fly through the water by flapping their huge “wings.”   Mammals in the ocean There are three groups of mammals in the sea: whales and dolphins,  seals and sea-lions, and  some rare sea mammals called sirenians, which include the manatee and the dugong...

The world is a dangerous place for most animals. Many need to defend themselves against other animals that want to eat them. Definition of prey An animal that is hunted, killed, and eaten by another is called prey.  Definition of predator Animals that hunt prey are called predators. Predator prey relationship examples Some animals are able to disguise, or camouflage, themselves as a protection against predators. But there are many other ways in which an animal can defend itself. One species of lizard, the leaf-tailed gecko of Australia, has a tail that looks like its head! You can imagine how confusing this must be for the lizard’s enemies. If a predator grabs this gecko by the tail, the tail breaks off, and the gecko can escape. Later, a new tail will grow. Birds that nest on the ground are usually camouflaged. Goatsuckers (also known as nightjars) and whippoorwills look like a pile of dead leaves. Ringed plovers look like the pebbles on the beaches where they nes...

Generally bears enter hibernation in early October and emerge sometime in April or May. 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. For animals big as the bear it is extremely difficult to find enough food during the winter, and therefore they go into hibernation. Yet in order to survive this long period of hibernation, the bears must previously build up their body weight by accumulating fat.  Hibernation cycle is just another unique natural adaptation that allows the animals like the bear to survive during severe wintertime.

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, sleeplike 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. Do Raccoon's Hibernate in Winter? We might say that the raccoon's do not truly hibernate during the cold winter days, but they rather "hole up" for days, weeks, or even months, depending on the weather. Raccoon hibernation is more like torpor, meaning their heartbeat, temperature, and body activities slow down, and they are...

Vertebrate animals have a spine, or backbone, and a cranium (brain case).  The spine is a long column of bones called vertebrae that run all the way along an animal’s back. Most vertebrates have vertebrae made of bones. Some, like sharks, have vertebrae of cartilage. We can feel our vertebrae by running our hand down the back of our neck and between our shoulder blades. Can you feel a row of hard, bony lumps? They run all the way down to your bottom. Every animal in the six classes of vertebrates - bony fish, cartilaginous fish, amphibians, reptiles, birds and mammals - has a spine or backbone. What does the backbone do? The backbone has a very important job to do. Every vertebra that makes up the backbone has a hole in the middle, and is joined to the next by a rubbery pad of cartilage. The backbone is like a flexible, hollow tube. Through the middle of this tube runs the spinal cord. The spinal cord is a thick bundle of nerves that carries messages from a...

1. You need: 2. Draw a map of an imaginary island. 3. Draw and invent names for these things on your map: 4. Draw some dangers on the map: 5. You are Alabama Smith or Vicky Vermont. How did you find the treasure? Draw your route on the map in black pen. 6. Write your story. 7.Show your map to the class. Tell your adventure story. Explore more: Arts and crafts for kids Volcano School Project - Arts and crafts for kids... My Star File - Arts and crafts for kids... Treasure map for kids - Arts and crafts for kids... Wacky animal whizzer - Art projects for kids... How to Make a Paper Banger - Arts and crafts for kids... How To Make An Ant Farm for kids? - Arts and crafts for kids...

Who was Marco Polo? Marco Polo was the first European to travel to Asia and tell his story. His book, "The Travels of Marco Polo" is the most famous travel book in history. Marco Polo was born in 1254 in Venice. When he was 17 he traveled with his father and uncle to China. Their trip took three years. The Emperor Kublai Khan was surprised to hear that there were Europeans in China. He invited them to his palace and he gave Marco a job. Marco Polo worked for the Emperor for many years. He traveled all over China and he made many amazing discoveries. In Europe, people didn't have many things that he saw. People put black stones not wood on their fires. These black stones - or coal’ -came from under the ground. Chinese food was different from Italian food. Some of it was very strange but Marco Polo really loved two foods in China. One was ice cream and the other was spaghetti. He saw people with small glass circles in front of their eyes. The...

1. You need: 2. On one sheet of card draw a volcano. Colour it. 3. Cut across the top of the crater. Measure the cut. 4. On the other sheet measure and draw a column and cloud of lava. Cut it out. Colour the column red then black on top. Colour the cloud. 5. Scratch a volcano poem on the column with your scissors. 6. Put the column through the crater. 7. To make the volcano erupt, pull out the cloud. Show your class and say the poem. Explore more: Arts and crafts for kids Volcano School Project - Arts and crafts for kids... My Star File - Arts and crafts for kids... Treasure map for kids - Arts and crafts for kids... Wacky animal whizzer - Art projects for kids... How to Make a Paper Banger - Arts and crafts for kids... How To Make An Ant Farm for kids? - Arts and crafts for kids...