School Science Lessons
Primary Science Lessons, Year 5
2009-02-18
Please send comments to: J.Elfick@uq.edu.au
Suggested answers to the teacher's questions are shown within [square brackets].
Lessons
Animals Sea animals and plants Protect sea animals Corals and jellyfish, coelenterates Shellfish, molluscs Starfish, echinoderms Fish life cycle
Food chains in the sea
Energy Water wheel
Steam wheel 		How light travels Mirror reflects light Images with a lens Water drop magnifier Pinhole camera
Human body Breathing in and out Fingerprints Body temperature Feel our pulse Test our eyesight Digesting our food
Measuring Water finds its own level Rain gauge Wind speed and direction Describe clouds Push and pull forces Air pressure
Plants Germinate bean seeds Depth of seed Germinate maize grain Roots absorb water Leaves lose water Protect our mangroves
Rocks and soils Collect rocks Soil profiles Fertilizer trial
Mineral deficiencies
 Cover crops Rain on slopes Mulch garden soil
Substances Make clay pots Make potash
from ash 		Keep water clean Heated air expands Burn to make carbon Hanging magnets
Table of contents
5.1 Sea animals and plants
5.2 Protect sea animals
5.3 Corals and jellyfish, coelenterates
5.4 Shellfish, molluscs
5.4.1 Shellfish, molluscs
5.4.2 Shellfish, molluscs
5.5 Starfish, echinoderms
5.6 Fish life cycle
5.7 Food chains in the sea
5.8 Water wheel
5.9 Steam wheel
5.10 How light travels
5.11 Mirror reflects light
5.12 Images with a lens
5.13 Water drop magnifier
5.14 Pinhole camera
5.15 Breathing in and out
5.16 Fingerprints
5.17 Body temperature
5.18 Feel our pulse
5.19 Test our eyesight
5.20 Digesting our food
5.21 Water finds its own level
5.22 Rain gauge
5.23 Wind speed and direction
5.24 Describe clouds
5.25 Push and pull forces
5.26 Air pressure
5.27 Germinate bean seeds
5.28 Depth of seeds
5.29 Germinate maize grain
5.30 Roots absorb water
5.31 Leaves lose water
5.32 Protect our mangroves
5.33 Collect rocks
5.34 Soil profiles
5.35 Fertilizer trial
5.36 Cover crops
5.37 Rain on slopes
5.38 Mulch garden soil
5.39 Make clay pots
5.40 Make potash from ash
5.41 Keep water clean
5.42 Heated air expands
5.43 Burn to make carbon
5.1 Sea animals and plants
See diagram 9.44: Seaweed, Ecklonia
Be able to name many different plants and animals of the sea.
This lesson is designed to give children an appreciation of the great variety of plants and animals in the sea. Do not teach the children the scientific classification in brackets over the page. They should list as many different types of plants and animals as possible by visiting the seashore, looking at pictures in books and remembering their own experiences. You cannot see microscopic animals, e.g. Protozoa or microscopic algae, but sometimes these plants and animals can change the colour of the sea. Bacteria are also microscopic and they cause dead plants and animals to rot. Many large animals have a bony backbone made of a glassy substance called cartilage. Porpoises, hippopotamuses and whales are not fish, they breathe air, have hair and suckle their young, so they are mammals. Seaweed plants are large algae with no roots, stems, leaves or flowers, they can be red, green or brown. Tiny floating algae or animals are called plankton. Sea grass grows on banks outside mangrove swamps. It is an underwater flowering plant.
1. Give descriptions (characteristics) and name examples of different animals in the sea, e.g. soft sponges, corals sea anemones are like flowers, tiny, long and soft worms, animals with jointed legs (shrimps), shellfish (molluscs), spiny skins (starfish and sea urchins), have backbones and skeletons (vertebrates), plants (seaweed, sea grass). Show pictures or specimens. How many different kinds of plants or animals do you know? Draw one specimen of each kind of animal or plant.
2. Collection of dead specimens in dilute formalin solution or methylated spirit, do not kill any animals for your collection.
Animals and plants in the rivers and sea
1. Microscopic single celled animals [Protozoa]
2. Sponges (dead sponge skeletons found on beaches) [Porifera]
3. Corals, sea anemone, jellyfish [Coelenterates ]
4. Flatworms, under rocks in shallow pools [Platyhelminthes]
5. Roundworms, mainly parasites [Nematoda]
6 . Beach worms, bristle worm, tube worm [Annelida]
7 . Mosquito, diving beetle, cockroach [Insecta]
8. Shrimps, prawns, crayfish, crabs, barnacles [Crustacea]
9. Chitons, cowrie, cone shell, turban shell, ear shell, volute, helmet shell, sea slug, elephant snail, oyster, clam, mussel, squid, octopus [Mollusca]
10. Starfish, brittle star, sea urchin, beche-de-mer Echinodermata]
11. Shark, sting ray [cartilaginous fish] Perch, eel, sea horse [bony fish]
12. Frog, toad [Amphibia]
13. Snake, turtle, crocodile [Reptilia]
14. Sea gull, tern, frigate bird [Aves]
15. Hippopotamus, porpoise, whale [Mammalia]
16. Plants in the rivers and sea, Green, red and brown seaweed [Algae] Ferns [Pteridophyta] Raphia palm, sago palm [Gymnosperms] Mangroves, rushes, grasses [Angiosperms] Bacteria and fungi (cause rotting)
5.2 Protect sea animals
See diagram 9.307: Turtle
Be able to explain why you should treat sea animals as a renewable resource.
Use conservation campaign posters for a particular country. Before this lesson, think of some local examples of loss of natural resources, e.g. inshore fish.
1. Explain the meaning of the word "resource" to the children. It means something you can use when you need it. A forest is a resource for fuel wood. A river is a resource for stones, clay and minerals such as gold.
2. If a resource can keep producing something that you need, you say it is a renewable resource. A forest is a resource for fuel wood for many years provided you do not cut down all the trees. Stones, clay and minerals are not renewable, once you take them away they are gone. Living resources are renewable, a garden is a living resource that can produce food year after year.
3. Non-living resources are not renewable. Living resources are renewable if you use only some of it and let the rest grow and reproduce.
4. The animals in the sea are one of your greatest living resources. For a long time in the past people have eaten only some animals and let the rest grow and reproduce. The animals have remained a renewable resource.
5. Nowadays people catch too many sea animals. If you catch too many animals such as fish, porpoise and crab there may not be enough left to renew the resource. You should take just enough for your needs but let most sea animals grow and reproduce. Otherwise they will become a non-renewable resource and die out. This will be a great loss to future generations in your country. Recent government efforts in many countries focus on campaigns through various establishments and institutions to do and ensure systematic conservation of natural resources.
5.3 Corals and jellyfish, coelenterates
See diagram 9.305: Corals and jellyfish, coelenterates
Be able to identify these animals and explain that they all have the same basic structure.
Use different coral specimens and pictures or specimens of sea anemones and jellyfish. You can teach this lesson on a coral reef or in the classroom.
1. If you have seen pieces of coral and a coral reef. Explain that coral is made up of many tiny animals each of which has a coat of hard lime. The lime coats stick together to make the pieces of coral and the coral reef. The coral animals die leaving the dead coral made of lime. Show pieces of coral. Is it alive? [No.] Where did the coral animals live? [In the holes in the dead coral.] Can you name different kinds of coral? The coral animals are so small you cannot study them.
2. However, sea anemones are much larger, have soft bodies and are similar to coral animals. The sea anemone has three main parts: 2.1 tentacles that can catch food, 2.2 mouth, 2.3 stomach. Tentacles can kill small fish by stinging them with poison. Can you put a finger in a sea anemone's mouth? Sea anemones are called the "flowers of the reef" because they have bright colours. They live in rock pools and catch animals with their tentacles. Sometimes they pick up shells so they can hide. Sometimes there is a friendly fish that swims among the tentacles and does not get stung.
3. A jellyfish does not look like a sea anemone or coral animal, but it does have the same three parts: tentacles, mouth and stomach.
4. Look at the drawing of the coral animal cut open. Turn it upside down. Imagine the soft body swelled up with jelly. Now you have a jellyfish. Jellyfish float in the sea. They can sting fish with their tentacles then eat them. Jellyfish can sting people. Some of them glow at night. They swim very slowly.
5.4 Shellfish, molluscs
See diagram 9.305: Shellfish, molluscs
Be able to describe and name different kinds of molluscs, shellfish and land snails.
Use examples of molluscs, shellfish and land snails. Collect different kinds of shells or shellfish and land snails. You can also prepare the class for an excursion to the coral reef. A live land snail or a shellfish in a jar of sea water will interest the children. Little land snails (Limocolaria) can be collected at night or early in the morning. Shellfish are called Molluscs.
1. If you know an animal that has a soft body and carries its house on its back. [A land snail or sea snail.] Explain that their body is divided into three parts: head, foot and coiled stomach. The head has a mouth and eyes at the end of tentacles. The body can be pulled into a coiled shell. Sometimes the house has a door made of hard shell. They can move along using their big foot.
2. Snails are one kind of animal called molluscs. There are four different kinds of molluscs:
2.1 Snails, have a single coiled shell, e.g. land snails, cowries, ear shells, cone shells, auger shells, helmet shell, volute, baler shell, scorpion shell. Some have lost their shell, e.g. land slugs and sea slugs.
2.2 Chitons have flat plates instead of a shell, a small head and a big foot.
2.3 Bivalves have two flat shells joined by a muscle that can close them together, like clapping hands. Some can use the foot to burrow in the sand, e.g. scallop, cockle and muscle. Others are fixed in one place, e.g. oyster, clam.
2.4 A squid and octopus foot is divided into eight arms. They can swim by squirting water out backwards. The squid has a small internal shell and the octopus has no shell. How many kinds of molluscs can you find?
Extra Activity
Make a shell collection and name the types of shells from different localities.
5.4.1 Shellfish, molluscs
Be able to classify shells into groups based on observed similarities and differences.
Collect different types of shells and tell the children to bring some.
1. Give each group a pile of mixed shells.
2. Sort the shells into small groups. You must say why you put shells into a particular group. Do not tell the children how to do it. Let the children decide their own groupings.
3. Pick out one shell from a group. Why did you put it into that group? [Some possible answers: they look the same, same colour, same shape, same markings.]
4. Do you know the common name for each group? [Some examples include scallop, top shell, cone shell, snail shell, cowrie, clam.]
5. Arrange the shells in each group in order of size.
6 . Draw the medium-sized shell of each group in your book.
Extra Activity
Make a collection of shells for the class. Label the shells with common names.
5.4.2 Shellfish, molluscs
Be able to explain why you should protect shellfish.
Shellfish are molluscs. Molluscs have a body divided into three parts: head, a large foot, and coiled stomach in a shell. In this lesson the teacher should explain that shellfish are interesting animals that are part of the natural heritage. If they are all killed because more people are eating them or selling the shells then something that you all own would be lost. Some shellfish appear on postage stamps: Cowrie, Trochus, Glory-of-the-Sea, Bailer Shell, Pearly Nautilus, Conch, Venus Comb (Murex) Triton.
Shellfish are valuable for four reasons:
1.1 They are part of the food web, plants and animals depend on each other for food and shelter. These plants and animals have lived in the local natural environment for a long time because there is a balance of numbers. If you kill too many of one kind of plant or animal, you upset the balance and other plants and animals will be affected.
1.2 They are a source of valuable growth food. Yet the human population is increasing rapidly and some kinds of shellfish on the coast could all be eaten.
1.3 They are a source of money. Some shells such as Cowrie, Trochus and Glory-of-the-Sea can be sold to overseas buyers. Also tourists like to buy shells to remember the country they have visited.
1.4 They are a part of your natural environment for all people to look at and enjoy. These shellfish are part of your culture and history. your ancestors were famous for the inlay work in carvings using Pearly Nautilus shell. If all these shellfish were killed this traditional art work would be lost.
Before the lesson, tell the children to bring some shells.
1. Show the children the shells and pictures of shells. How many different kinds are there? Do you know their names? How are shells used at home? Do people eat them? [Yes.] Do people use them? [Yes, e.g. Baler Shell.] Do people sell them? [Yes, to tourists.] Do people make anything with them? [Yes, Mother-of-pearl inlay work for traditional decoration and to sell to tourists.]
2. Explain how shells are part of your natural heritage. They are something your ancestors owned, something you own, and something that should be still living for your children.
3. Explain the four reasons why shellfish are valuable for the:
3.1. food web
3.2. food
3.3. money in culture.
3.4. Explain why shellfish could all be killed:
4.1. There are more people now than before.
4.2 There are more canoes with outboard motors and people with diving equipment.
4.3 There are more people want to sell shells.
4.4 There are more foreign boats and tourists.
5. Explain how children can protect shellfish
5.1 Tell people about the importance and the danger of killing too many shellfish.
5.2 Tell children to watch foreign boat crews and tourists.
5.3 Not to kill the shellfish unless very hungry.
Extra Activity
Display of shell under the heading "Our Natural Heritage"
5.5 Starfish, echinoderms
See diagram 9.304: Starfish, echinoderms
Be able to identify and list the different types of echinoderms.
Use drawings and preserved specimens of types of echinoderms. The spiny skinned animals, called echinoderms are found only in the sea. They have a circular design, if you cut through the centre of their mouth in any direction the two halves look the same. Beside having spines in their skins or spines sticking out, they have hundreds of little tube feet to help them move along the bottom of the sea. The starfish usually has five arms and a mouth facing down. They can suck on to the shell of a bivalve mollusc such as an oyster, pull open the shells then eat the inside. Brittle stars have a separate round body and long legs that they can drop off when they are frightened. Sea urchins are globe shaped, have long spines and downwards facing teeth that can grind a hole in a shellfish. Beche-de-mer is an example of the sea cucumbers that have lost their spines. When frightened they spit out their stomach. Beche-de-mer or trepang is exported overseas for Chinese soup. Use specimens or pictures of these animals. The following groups of spiny skinned animals are called Echinoderms: 1.1 starfish, 1.2 brittle stars, 1.3 sea urchins, 1.4 sea slugs, 1.5 sea cucumbers, e.g. beche-de-mer.
1. Show drawings or specimens of these animals. What are their common features? [Shape, spiny skins, live on the sea bottom.]
2. Look at the starfish. Does it have a front or back? [No.] Are the arms different? [No.] How does it move? [With its tube feet.] What are the arms for? [To pull apart the shells of shellfish.]
3. Draw each different kind. The aim is to perfect observation and creativity in them.
Extra Activity
Collection of dead echinoderms, do not kill any animals on the reef.
5.6 Fish life cycle
See diagram 9.301: Life cycle of a fish | See diagram 9.302: Shark and fish
Be able to explain the life cycle of a fish.
Use illustrations of the life cycle of a fish. Bring some freshwater fish to class.
Show the diagrams of the life cycle of a fish to explain the following points:
1. A female fish lays eggs in the water and a male fish puts many sperm into the water near the eggs.
2. many eggs are not fertilized.
3. Only those that are fertilized become little fish.
4. Many little fish are eaten, so only a few grow into adult fish.
5. The female fish must lay thousands of eggs if some are to grow into adult fish.
Extra Activity
Examine closely the adult fish. Can you see any differences between the male and female fish Can you draw the differences?
5.7 Food chains in the sea
Be able to explain the importance of keeping the food chains in the sea unbroken.
Use plants and animals in the environment and in the sea. In this lesson children should understand that all plants and animals in the sea are important because they are related by food chains. Plants and animals depend on each other for food and when they die their bodies are rotted by bacteria to be used by simple plants and animals again. You can think of the food chains usually or by particular examples. An example of a food chain is seaweed is eaten by a shellfish is eaten by a fish is eaten by a bird. Seaweed Shellfish Fish Bird When each of these animals dies, the material in their bodies decomposes and can be used by the seaweed again. However, if you eat all the shellfish or fish then the food chain is broken. Usually plants are eaten by animals are eaten by larger animals are eaten by larger animals. If ">>" means "is eaten by", you can show a food chain as: plants >> small fish >> big fish >> shark >> man
If you kill all the animals or plants in any step of the food chain then the food chain is broken and all the living things in the food chain are affected.
1. Give examples of living things in the sea eating other living things, e.g. smaller fish eaten by sharks. Write all the examples on the chalk board. So far you have steps in the food chain, tell the children to tell you a third or fourth step, e.g. seaweed, fish, shark, man.
2. Can you make different food chains? Can you make food chains with many steps? Try this with the children and write the steps on the chalk board.
3. What is passed along the food chain? [The material in the bodies of the plant and animals.] What happens to the materials when the plants or animals die and are not eaten? [They rot.] Is the material of their bodies lost from the food chain? [No, simple plants and animals can use it again.]
4. Show the general food chain. Plants fish one fish two shark
5. The dotted lines show the bodies of dead plants and animals made rotten by bacteria then used by plants again. What would happen if you caught all the fish? [There would be no food for fish two and later no food for the sharks. The food chain would be broken.]
6 . Name any kinds of animals or plants in the sea that could be wiped out by too much fishing or hunting. How many animals of the sea should you catch? [Catch some but do not catch so many to break the food chain.]
Extra Activity
Discussion with an old fisherman or fisheries officer on whether there are as many fish now as before. Are some food chains already broken? Visits to agricultural departments (fishery section) can help us to find out more about this.
5.8 Water wheel
See diagram: 4.3.2
Be able to make a water wheel and show how moving water can turn a wheel.
Use water, hose, or water in a bucket. The wheel can be made in any of the following ways:
1.1 Use thin bamboo, with thin pieces of tin or cardboard for the blades and a smooth stick for an axle.
1.2 Use pawpaw stalks instead of bamboo with a smooth stick for an axle.
1.3 Cut a small square of coconut husk. Make a hole in the middle with a hot nail. Push the pieces of tin in the sides. Let it spin on the nail or a smooth stick.
1.4 Cut a round piece of paper or taro stem. Stick very stiff leaves round the edge. Spin on a smooth stick.
1.5 Stick Plasticine (modelling clay) around a piece of bamboo. Stick cardboard or tin pieces in the Plasticine. Spin on a smooth stick.
1.6 Use an empty cotton reel and tin sheets. Spin on a nail.
1. Give out the materials and show how to make their water wheels.
2. Put the wheel in running water under a tap or by pouring water over it. What happens? [The wheel turns when the water hits the blades.] Increase the speed of the water. What happens to the water wheel? [It turns faster.]
3. What happens when the wheel is placed in running water. [It turns or spins.] What happens if you increase the speed of the water? [The wheel turns faster.] How can you increase the speed of the water? [By opening the tap more, by making the water fall further.]
4. Collect the water wheels and keep them for the lesson on Steam Wheels.
Extra Activity
Water wheels are used to generate hydroelectricity. the electrical generator is often placed at the bottom of a water fall and water is lead to it in a pipe from the top of the waterfall.
5.9 Steam wheel
See diagram: 9.3.3
Be able to show that steam can turn wheels.
Use water wheels from previous lesson on water wheels. Cans with tight fitting lids with a small hole in the lid. Burners, heating stand and water. Make the holes in the tin lids with a nail. Do not put too much water in the tin as it will take too long to boil and produce steam. About four cm should be enough.
1. Give out the materials and tell the children to pour water into the can and then fit the lid on tightly. Place the can of water on a heating stand. Light the burner and heat the water.
2. When the water is boiling tell the children what is coming out of the hole in the tin lid. [Steam.]
3. Take it in turns to hold your water wheel over the hole in the lid as shown in the diagram.
4. What happens? [The wheel turns.]
5. What is formed when water boils? [Steam.] What causes the wheel to turn? [Steam.] Which can turn a wheel faster, water or steam? [Steam.]
6. The wheels of a steam engine are turned by steam. Steam engines are used to make electricity, drive trains and boats. Wood or coal is burnt to heat water to produce the steam. Steam boats and trains are not common now. However, in many countries most of the electricity is made from burning coal in steam engines that turn on electric generators.
Extra Activity
Draw pictures of steam engines used in boats, trains and power stations.
5.10 How light travels
See diagram: 28.1.1.5
Be able to show that light travels in straight lines.
Use 3 pieces of cardboard about 25 cm x 25 cm for each group, candles or a torch or a mirror to reflect sunlight, jar of water, chalk dust, piece of string, rubber tubing or pawpaw petiole about 50 cm long. Light is invisible, it cannot be seen. Completely transparent substances, like air it also cannot be seen because you allow all light to pass through them. You cannot see light passing through air or water unless the air or water has something in it, e.g. chalk dust, street dust that will reflect the light into your eyes
1. Use a pin to cut a hole in three pieces of cardboard. Hold each piece of cardboard about 10 cm apart. Thread a piece of string through the holes and pull very tight. Place a candle in line with the string. Take away the string and tell the children to look through the hole at the candle.
2. Can you see the candle? [Yes.] What would a line from your eye through the holes to the candle look like? [A straight line.]
3. Move one piece of cardboard. Can you see the candle? [No.] Why not?
4. Put some chalk dust in a jar of water. Shine some light through it. How does the light travel? [In a straight line.] Can light bend? [No.] Can light go around corners? [No.]
Extra Activity
How can you see around corners With a mirror, the light still travels in a straight line.
5.11 Mirror reflects light
Be able to show how light travels when it is reflected by a mirror.
Use mirrors, cardboard and scissors, shiny surfaces, e.g. aluminium foil, tin lids, rubber ball. Practice before the lesson with the recommended materials.
1. Give out two mirrors and different shiny surfaces to each group.
2. Use a mirror and shiny surfaces to reflect a beam of sunlight along the floor, or the ground or along the top of a desk. Which things reflect the light best? [Materials with smooth shiny surfaces.]
3. Use scissors to cut a slot out of your piece of cardboard, to put the slot over the beam of light.
4. Turn the second mirror to reflect the thin beam of light to the left, to the right, up and down.
5. Tell one child to stand against a wall holding the second mirror to the chest. Another child should reflect light on to the second mirror from the first mirror. A third child can then see the reflected light. Tell another child to throw a rubber ball from the first mirror at the wall behind the second mirror. Where the ball goes. [It bounces off the wall in the same direction as the light.] Reflection occurs when light bounces off shiny surfaces.
Extra Activity
Place two mirrors at right angles and a bottle top between. How many reflections are there?
5.12 Images with a lens
See diagram: 28.1.1.5
Be able to form an image on a screen using a lens and can describe the image and measure its distance from the lens.
Use candles or flame, white paper for screens, you can rub some cooking oil on the paper to make a better screen, magnifiers. You should darken part of the classroom. Formation of images on screens and distance measurement are the real focus of this lesson.
1. Put the candle, lens and screen in a darkened area so that the image of a candle can be seen on the screen. Place the lens at 10 cm from the screen to get the sharpest image.
2. Describe the image. [Small and upside down.] What happens when you move the lens closer to the candle? [The image gets larger and is still upside down.] When the size of the image is about equal to the size of the candle flame. [When the lens is about half way between the screen and the candle.]
3. Look at images of objects outside the classroom. Describe them. [The images are smaller than the objects and they are upside down.]
4. Lenses are found in eye glasses, cameras, binoculars, projectors.
Extra Activity
Where is the screen in your eye? [The screen is at the back of the eye, the lens is at the front of the eye where light enters. So in your eye the distance between the screen and the lens stays the same.]
5.13 Water drop magnifier
Be able to make a water drop microscope and use it to describe the structure of small objects.
You need a piece of cardboard and a piece of sticky tape. Punch a hole through the sticky tape and the cardboard. Put a drop of water on the hole to make a water drop microscope. To use the microscope attach it to a ruler at with sticky tape, put some hair or a leaf on the paper, look down through the water drop and move the pencil between the book and paper.
1. Show the curved surfaces of their magnifying lenses. [Glass with a curved surface can magnify, make things bigger.] that you are going to make a curved shape out of water, a kind of lens.
2. Show how to make the water drop microscope. Show how to set up the water drop microscope. Look at the shape of the drop very carefully.
3. Put a small printed word under the water drop microscope. Write this word at the size you see it.
4. Move the microscope up and down. Focus it until the printed letters look bigger. The children may have to remove a little water from the drop with their fingers until the printed letters look bigger.
5. Put a little bit of sugar on their paper. Spread the sugar under the microscope and then observe it.
Extra Activity
Look at different things using your microscope, e.g. soil, ants, roots, feathers.
5.14 Pinhole camera
See diagram: 28.9.0
Be able to make a pinhole camera and describe the difference between the image and the object.
Use paper screen, nearby objects. Make a pinhole camera before the lesson. An image is the picture of an object on a screen. The image of a pinhole camera on a screen is upside down.
1. Show your pinhole camera.
2. Make a small hole in the bottom of the tin using a nail. Cover the open end of the tin with a piece of thin paper, e.g. typing, tracing or greased paper. This is the screen on which the picture will be formed. Use a rubber band or a piece of string to hold the paper on the tin. Tie a piece of newspaper around the tin to form a tube. This makes the screen dark. The picture is easier to see in the dark.
3. When the children have made their pinhole cameras tell the children to point them towards the door or windows. Let the children look at trees, buildings through their pinhole cameras.
4. This is how a real camera works except that the paper screen is the film covered with light sensitive substances.
Extra Activity
Measure height of object / height of image, and distance from object to pinhole / distance from pinhole to screen.
5.15 Breathing in and out
Be able to observe what happens to your bodies when you breathe in and out.
Use a watch with a second hand, bucket with a handle. This lesson is designed with two aims:
1.1 To give children more experience in observing their breathing mechanism and so be able to improve observation of their own bodies.
1.2 To learn about the importance of oxygen gas (O2) to the body. Use a watch with a second hand or you could count seconds "one and two and three and four".
1. Sit quietly watching you. What they are doing? [Nothing, they are just sitting still.] They are not doing anything. They are breathing in and out. Did they realize they were breathing? [No.] What made them breathe in and out. [You don't know.] Your brain makes you breathe in and out. They don't have to think about it. It is automatic.
2. Sit quietly watching you. Tell the children to close their mouths, hold their noses and stop breathing. They will count to 100, then they can start breathing again. Give the order and start counting. When do they start breathing again? [After 20-30 seconds.] Why they didn't wait until the count of 100. [You had to breathe again.] What made you breathe again? [The brain.]
3. Breathe in and out very deeply 20 times. Then say "Stop" and start counting. How long can you hold your breath now? [About one minute.] Why can you hold your breath longer? Explain that when you breathe in and out your body takes in oxygen gas from the air. your body needs oxygen gas. If you breathe in deeply your body stores some oxygen gas in the lungs so you can hold your breath longer.
4. Push one finger up under the lowest right rib. Breathe deeply in and out. What happens to their ribs when you breathe in? [They rise.] Show the bucket. If your rib is like the handle of the bucket, when you breath in it is like raising the handle of the bucket. When you breathe out, the handle of the bucket goes down. Feel up under your ribs again and breathe in deeply. What happens to your finger when you breathe in? [It is pushed down.] What pushes it down? Explain that a big muscle called the diaphragm pushes the finger down. If you run a long way, you may get a pain in your diaphragm called a "stitch".
5. If the chest gets bigger or smaller when you breathe in. [Bigger, the chest expands.] What part of the chest moves? [Two parts, the ribs turn up like a bucket handle and the diaphragm pushes down.] When you breathe in where does the air go? [Into the lungs.] Where are the lungs? [There is one on each side of your chest.]
6. Why do you breathe in air? [Our body needs oxygen gas.] At the start of the lesson why were you breathing quietly? [You do not need much oxygen when you are sitting quietly.] What happens to your breathing when you start running? [You breathe in and out more quickly and deeply.] Why do you breathe more when you are running? [The body needs more oxygen gas.]
Sentence Completion: your body needs [oxygen] gas. When you breathe in, your body gets oxygen gas from [the air]. You breathe [slowly] when you are sleeping or sitting quietly because you do not need so much [oxygen gas]. When you are running, you need much oxygen gas so you breathe [quickly].
Extra Activity
1. Breathe in and out rapidly through your nose and through your mouth. What do you notice? [The nose warms the air before you breathe it in.]
2. Close your mouth and hold your nose then try to breathe out. What do you notice? [Pain inside the ear.] This is the air pressing against skin in the ear called ear drums. If you swallow, the pain will go away. They may feel this pain when you are in a landing aircraft.
5.16 Fingerprints
See diagram 9.233: Fingerprints
A. Be able to describe their fingerprints.
You will need a stamp pad, magnifiers soap and water.
If you do not have a stamp you can use carbon paper or make carbon paper from aluminium foil:
1. Use a piece of aluminium foil or silver paper. 2. Hold it in a candle flame so that the lower side becomes covered evenly with a layer of carbon. 3. Test the carbon foil you have made. It is like carbon paper. You can use it to make fingerprints.
1. Look at the skin on your finger tips. There are lines on them. Look for lines with the shapes in the diagram: whorl, loop, arch
2. Make a print of your thumb use a stamp pad or pour some ink onto absorbent. Press your thumb onto the inky paper. Wet it all over with the ink. Then press your thumb onto a sheet of clean white paper.
3. Look carefully at the thumb print. Look for arches, whorls, and loops.
4. Look at the thumb prints of other children. Are any prints the same? [No] Police use finger prints to identify people.
Extra activity
Lengths of fingers
1. Measure the lengths of your fingers as shown in the diagram.
2. Calculate the ratio: length of middle finger/length of little finger.
3. Is this ratio the same for all children? Is it the same for boys or girls?
B. Be able to describe and compare fingerprints among human beings.
Use ink or stamp pads, magnifying glass. This lesson is designed to train children in the skills of description and comparison. Also it is interesting because police use fingerprints to identify people. No two people in the world have the same fingerprints.
1. Explain how police use fingerprints. If a robber breaks into a house he leaves invisible fingerprints on anything he touches, e.g. door handle. The police can put a special powder on the door handle and record the fingerprints. Later the police can catch a man who could be the robber. The police put ink on the man's fingers and take the fingerprints. Then they compare the man's fingerprints with those they took off the door. If the fingerprints match then the police have caught the robber.
2. Give each group some ink or a stamp pad. Put the ink on the thumb then press the thumb on the paper. Hold the fingerprint up to the light and look at it with a magnifying glass.
3. Fingerprints can be described: 3.1. whorls, 3.2. loops, 3.3. arches
Draw the outline of your thumb. Draw in the whorls, loops and arches.
4. Make fingerprints of your other fingers. Do they have the same pattern as your thumb? [No.]
5. Compare the fingerprints of different children. Are they the same?
Extra Activity
Fingerprint Game: Each child in the group makes two sets of fingerprints. The teacher takes one set, then gives back one print of the "robber". Now compare the "robber's" fingerprint to all the fingerprints. Who is the "robber"?
5.17 Body temperature
See diagram 22.02: Clinical thermometer
Be able to measure the temperature of your body using a clinical thermometer.
Use a clinical thermometer. You must use a clinical thermometer and not any other type of thermometer. You will also need a glass of water with some antiseptic in it. Make sure that you can read the thermometer. Normal body temperature is marked with an arrow of 37oC. In a clinical thermometer there is a constriction in the bore. This allows the mercury to expand (rise) showing a rise in temperature but it does not allow the mercury to contract (fall) again. This lets you take a thermometer out of a patient's mouth and does not give a falsely low reading. To move the mercury down again you have to flick the thermometer with a quick turn of their wrist. Practise flicking it to make the mercury go down. Do not drop it on a concrete floor. Practise flicking the mercury down standing on the grass. Do not be alarmed at small differences in temperature between people. In women, the body temperature changes with the menstrual cycle.
Take the temperature of each child in the class.
1. Show the clinical thermometer. Have they seen it before? Explain that this measures how hot your body is. In healthy people the body has a constant temperature: 37 degrees Celsius (37oC) but it can vary slightly. It is lower when you wake up and it is higher if you run about a lot. If the body temperature is much higher or lower this means that you are sick.
2. Draw the scale on the chalk board.
3. Take your own temperature. Draw an arrow on the chalk board diagram to show your own temperature, e.g. 37.2oC.
4. Flick down the mercury. Wash the thermometer in antiseptic then read the temperature with each child. Tell each child to draw an arrow on the chalk board to show your temperature.
5. Look at all the arrows. What conclusion? [The average temperature is 37oC, some temperatures are a bit higher or lower.]
Extra Activity
Compare these two groups of temperature readings:
1. Adult / child / babies
2. Boys / girls
3. Lying down after running around the classroom. Make a table and compare your readings for each group. Besides this you could try outside the class by going to a nearby Health Centre or hospital to collect information on temperature readings.
5.18 Feel our pulse
See diagram 9.239: Feel our pulse | See diagram: 9.239.1: Electrocardiogram
Be able to feel your pulse and notice how it changes with different body activity.
Practice feeling your own pulse. How many beats of your pulse per minute? [About 70.]
1. Children must be seated quietly and not move about.
2. Put your forearm on the desk, palm up with the wrist on the edge of the desk and hand in the air.
3. Press the four fingers of the other hand down on the side of the wrist. Wait a little while, keep still, and you will feel the pulse. Start counting the pulse.
4. Now tell the children to run around the classroom and feel the pulse again. [It is faster.]
5. The pulse tells us how fast the blood is pumped around the body. If you are sick or after a big meal it is faster, when you are asleep it is slower.
6 . Roll up some paper to make a tight tube. Hold it against the chest of another child. Press your ear against the other end. Can you hear the heart pump the blood?
Extra Activity
Use a watch to tell the children when a minute starts and stops. Write down your pulse rates on the chalk board in beats per minute. What is the average pulse rate?
An electrocardiograph records the electric currents generated by the the heartbeat and records them on an electrocardigram.
5.19 Test our eyesight
See diagram: 28.1.1.6
Be able to test your eyesight.
This lesson is designed to give children experience in measuring eyesight and comparing the eyesight of different children. It is different from the eyesight test used by doctors. Use the "E" chart over the page. Cut out a big "E" from a piece of cardboard or tell the children to cut out the big "E" during the lesson or the children can make an "E" shape with their fingers.
or groups of four
1. Draw a line on the floor five metres from the teacher's chair and parallel to the front of the teacher's desk. Stand on the line facing you. Show the chart. Point to the top E. The child has to hold the E in the same position or make the same E shape with the hand.
2. What is the lowest line in the chart where the child can see the positions of the E? If you can see the bottom line, you should move one metre away and start again. If you can't see the bottom line, you should move one metre closer.
3. Test all the children again. Which child has the best eyesight?
4. Do the test again with one eye closed, then test the other eye. Is one eye stronger than the other?
Extra Activity
Draw a chart of white E's on a black background. Are they easier to see or harder to see than the black E's?
5.20 Digesting our food
Be able to observe and discuss what happens during digestion by examining an animal's stomach.
Use food, chicken or rat, scissors and knife, chloroform solution and lens. The teacher has to recall the methods of studying internal organs of animals by means of dissection.
1. Digestion of food is in two stages:
1.1 Breakdown of food into smaller parts using teeth and tongue in the mouth.
1.2 Softening of the food by saliva in the mouth and acid in the stomach.
2. Let the children bite a dry biscuit. Their teeth and tongue will break it into smaller pieces. Soon it tastes sweet because the saliva changes starch into sugar.
3. Kill a chicken or toad and show the stomach. It is like a bag made of hard muscle. This muscle can mix the food with acid. 4. Cut open the stomach with scissors. Turn the stomach inside out and show the digested contents.
5. Wash out the inside of the stomach and let the children examine it with a magnifier. Can they see the folds in the walls?
Extra Activity
Show the inside of a cow's stomach called tripe. You can buy this in a butcher's shop. Compare the size with the stomach of a rat or rabbit.
5.21 Water finds its own level
See diagram 12.0.0: Water levels
Be able to show that the surface of water is always horizontal.
Use plastic tubing, ruler or metric stick, hose, water. The depth of liquid in a vessel remains the same and does not depend on the shape of the vessel containing it.
1. Give out empty plastic tubes, water and rulers. Pour some water above the desk in each arm. What the difference is in height? [No difference.] Pour some more water in and measure again. What is the difference? [No difference.] Draw a tube showing the level of the water and the horizontal line joining the level.
2. Hold one arm of the tube vertical then move the other arm apart keeping it vertical. What happens to the height of the water in each arm? [It drops a bit.] Compare the height of the water in each arm. [They are the same.]
3. Keep one arm of the tube steady, then bend down the other arm. What happens to the height of water in each arm? [The height drops the same in each arm of the tube.]
4. Put your finger over the left hand end of the tube. Then bend down the right hand end. What happens to the water level? [It goes down as you bend the tube.] What happens to the water level in the left hand tube? [It does not change.] Are the levels still the same? [No.] Why not? [The finger in the left hand end blocked the tube so no air can get in or out.]
5. Go outside on a slope. How you can find two places at the same level? [Use two rulers and the hose or long plastic tube.] B is five cm lower than A. A is five cm higher than B. [if the height of water in the tube is 10 cm at A and B, what is the difference in height at A and B? [The same height.] If the height of water at A is 10 cm and at B is 15 cm, what is the height at A and B? [B is five cm lower than A.] If the height of the water at A is 10 cm and at B is five cm, what is the height at A and B? [B is five cm higher than A.]
6 . Using this tube, you can mark a horizontal line around a hill or along a slope. This line is called a contour. Mark a contour line along a slope.
Extra Activity
Making contour banks to prevent soil erosion. Mark a contour line along a slope or around a hill. Dig a drain at the same depth along the contour line and use the soil to make a contour bank on the down side. Pour some water in the contour ditch. It should not flow along because the bottom of the ditch should be horizontal. The water should just spread out. Contour ditches and banks can stop soil being washed down by the rain. You can stop soil erosion. If the height of the stick at A is three metres and at B is 1. 5 m, how does the ground slope A From B to A? [B is 1. 5 m above A.]