Module 3: Science - energy and movement

Section 1: Everyday forces - investigating movement

1. Discussing Forces in everyday life

How do you, the teacher, find out what your pupils already know about forces and motion? And how can you extend these ideas and link them to current scientific understanding?

In Case Study 1, a teacher raises her pupils’ awareness of all the force events around them. From the start, she challenges their understanding by asking them to see themselves as thinkers with scientific minds.

In Activity 1, you ask pupils to identify and describe forces at work captured in photographs. By trying to make sense of what they have identified, they will be increasing their science awareness with your help.

2. Using games and brainstorming to learn about forces

Forces and motion are part of the games and sports children play.

You can use this to determine what your pupils already know and to encourage them to challenge their own thinking. By doing this, they will be extending their understanding.

Case Study 2 shows how pupils can learn things about force and motion through games and competitions.

Activity 2 builds on pupils’ identification of forces from Activity 1. We integrate science and language work to help us describe forces and their effects more accurately in a brainstorm activity. (See Key Resource: Using mind maps and brainstorming to explore ideas.) There are no ‘right’ or ‘wrong’ answers in a brainstorm, but you are challenging pupils’ thinking by encouraging them to speak their thoughts. An important part of learning in science is communicating ideas and practising using scientific vocabulary.

3. Organising investigations in to friction

Resource 4: Summary of forces summarises what a teacher could be expected to understand on forces and motion.

Primary pupils need to experience a range of practical experiences and have chances to talk and think about what they have been finding out. There are many activities that would extend your pupils’ ideas about forces, for example looking at balls rolling down slopes at different angles and pushing or pulling shoes along different types of surface.

Case Study 3 shows how Mr Akinbiyi reflects on what he has achieved with his class. How do you reflect on your learning and that of your pupils? What would you record about your learning in this topic?

In the Key Activity, you guide the pupils through thoughtful investigations around a force that slows objects down – friction. This extends the work of Activities 1 and 2, where you encouraged pupils to speak their ideas. At the same time, you can assess their developing understanding by listening carefully to what they say.

Resource 1: Finding forces in pictures

 Teacher resource for planning or adapting to use with pupils

Original source: Science Now Book 1 – Heinemann

Resource 2: Force Games

 Teacher resource for planning or adapting to use with pupils

The standing one-hand boot throw

A competitor stands outside in the open with both feet on an agreed line with a large size boot, which they proceed to throw as far as possible, without moving their feet.

• What is the best way to measure/compare distances?
• Is this a push or a pull?

Discuss other examples, like throwing a 1.5 m stick or heavy stone. Explain that these are like sports activities such as javelin throwing and shot put.

Wrist wrestling rules

Opponents face each other on opposite sides of a desk with left hands on laps. Their right elbows are on the table in front of them in line with the opponent’s elbow (elbows should not move). They grasp hands and at the instruction ‘PUSH!’ each tries to push the back of their opponent’s hand onto the table to score a point. First to three is the winner who then accepts further challenges. (A variation is to alternate hands.)

This is a good example of balanced forces, but as one weakens, the more powerful force results in a movement.

Blow football

Blow football is played on a large empty table with a ping-pong (table-tennis) ball and two or three players per team. The ball can only be moved by air blown through straws.

A goal is scored when the ball is blown over the far end of the table. A game lasts five minutes each way. If the ball goes off at the side, the opposite team has a free blow-in from the place where the ball left the table. If the ball is touched by a player or a straw, the opponents get a penalty blow and all other straws must be at least two straw lengths away.

This is an example of pushes on the ball from the air.

Tug-of-war

Two opponents stand sideways, foot to foot. They hook little fingers together. At the command pull, they both try to pull the other off balance. The first person to move or lift a foot is the loser.

All these games show the effects of forces clearly and give pupils a good chance to experience and think more carefully about how forces operate. Many other possible push and pull games exist and new ones are waiting to be invented.

Resource 3: Force word spiders or burrs

 Example of pupils' work

Here are some examples of pupils’ work.

Resource 4: Summary of forces for the teacher

 Background information / subject knowledge for teacher

Adapted from: Developing Subject Knowledge – Jane Devereux

Resource 5: How can we reduce friction?

 Pupil use

Friction is the force that stops your shoes from sliding across the floor. This helps you not to slip over. But sometimes we want to reduce the amount of friction – how can we do this?

Work with your partners to complete this planning sheet for your investigation.

Our investigation:

Our results:

Try to draw a table to record your results.

Resource 6: More ideas for experiments around forces

 Teacher resource for planning or adapting to use with pupils

1. Using springs to measure forces:
   • Make a class list of everything the pupils have seen that includes a spring.
   • Show how a spring stretches with a pulling force and measure how much it stretches.
   • Use a spring to measure forces around the classroom – measure how much the spring changes in length. (You can make a spring from a 50 cm length of copper wire or you can use a strong elastic band instead of a spring.) Some forces to measure include door opening, pulling a chair along the floor, pulling a pen or pencil, opening a clothes peg.

2. Cutting down friction in water – making streamlined shapes:
   • Ask pupils to draw the shapes of fish, boats and diving birds. Which sort of shape is best for going fast through air or water?
   • Pupils make different shapes with lumps of clay or plasticine. Drop these shapes through a tall tank of water and time how long it takes each to get to the bottom.

3. Forces at a distance:
   • Use a magnet to pick up steel pins. Ask pupils to slowly move the magnet towards the pins. What is the distance between them when the pins first start to move?
   • Rub a plastic pen or ruler on a cloth (e.g. a duster). This gives the pen or ruler an electric charge. Now try to use the pen or ruler to pick up small pieces of scrap paper. How many will it pick up?
   • Ask pupils to explain what they think is happening in each of these experiments.

4. Forces and weight:
   • Weight is a special sort of force caused by the Earth attracting everything on it or near it.
   • Ask pupils to use a spring or elastic band to make a weighing machine that measures the pull of the Earth on objects. They will need to make a scale for it.
   • Then talk to pupils about how the weight of these objects would be different on other planets in the solar system or on the moon. Larger planets exert a larger force on another object and smaller planets or bodies exert a smaller force.

Section 2: Exploring sounds and music

1. Using stories and games to introduce sound

It is always wise to start by finding out what pupils already know. Pupils will recognise many different sounds, but they probably haven’t considered different qualities of these sounds like pitch (low notes or high notes) and volume (loud or soft).

In Activity 1, you play a guessing game with your pupils, where they try to identify sounds and explain how they think the sounds were made. This involves pupils scoring their own answers, one way of involving them in assessment.

Don’t dismiss answers that seem incorrect – encourage pupils to explain their responses. You can learn much about their understanding from what they say. Afterwards, think about what they said – was there anything that surprised you?

Case Study 1 shows how one teacher used a local story as a starting point for pupils’ questions about sound. Do you know any stories from your own culture that you could use? Or could you ask a member of the local community to visit your school to tell a story? Could one of your pupils tell a story?

2. Working in groups to investigate sound

Sounds are made by vibrating objects. The vibrating object causes the air particles to move closer together (compress) and then apart in a regular pattern – this is called a sound wave (see Resource 2: Sound waves). Thus the air carries the sound to our ear.

In Activity 2, you ask your pupils to use everyday objects to make sounds and see how they can change these sounds in different ways. The pupils should carry out this investigation in small groups. (See Key Resource: Using group work in your classroom.) Spend some time at the end of the investigation talking to your pupils about how the groups worked; do they have ideas about how they could work together more effectively in the future?

In Case Study 2, a teacher uses an interesting set of questions to encourage pupils to think about their work – another way of involving them in assessment.

3. Exploring musical instruments

For centuries, people have developed musical instruments using local materials. These all involve plucking, hitting, blowing or rubbing to create vibrations of different pitch and volume. Many instruments also have a box of vibrating air to amplify the sound (make the sound louder). Try to find out about traditional instruments in your community – is there anyone who could come into your classroom and show their instrument?

The Key Activity and Case Study 3 involve pupils exploring musical instruments – either from the community or those pupils have made themselves. In both cases, pupils develop criteria to judge the instruments. In the activity, you could also ask your pupils to develop criteria to judge their presentations.

Inviting local musicians into the school to demonstrate their instruments and to hear the pupils’ instruments would be a wonderful way to end the activity. (See Key Resource: Using the local community/environment as a resource.)

Resource 1: Sound story

 Teacher resource for planning or adapting to use with pupils

The swallowing drum

A small girl, an only child, lives with her parents in a certain village. Because of a terrible unspoken local danger, she is never let out of her parent’s sight nor allowed to go and play with other children. She feels like a prisoner in her own home and longs to be independent like the other children.

One day, she gets a chance to slip away when her father falls asleep after lunch. The mother has gone to work in the fields and the girl hopes to surprise her there. She is not certain of the way and when the path splits into two, she chooses the cool path by the river rather than the hot path over the hill.

After a while she comes across a small little drum, beating itself …

But the little girl is curious and she carries on regardless. Around another corner she comes across a middle-sized drum beating itself …

But the little girl is curious and she slips past the drum and carries on. Further on, what do you think she finds? Yes, A big drum beating itself …

Really curious, the little girl ignores this warning too. The path comes to the edge of the forest and as she enters the dark forest the trees close behind her.

She can only go on now – but there is a terrible drumming noise in the forest. She comes to a clearing and faces a truly enormous drum. It is the swallowing drum – the terrible danger that her parents were so terrified might get her. She gets swallowed by the drum and, as she falls to the bottom, other people and animals rush up asking her if she has anything sharp with her. But she hasn’t. All she can see as she looks up from her new prison is the slit of the mouth of the drum and a huge wooden heart beating …

Back home her parents are devastated when they discover her missing and see where her footprints lead. The father weeps and cries and covers himself with ashes from the fire. But her mother doesn’t rest – she goes around the village borrowing sharp things and she stays up the whole night stitching them carefully into the inner lining of her cloak.

The next day she sets out for the forest. She sees no drums but as she enters the forest, the trees close behind her.

She comes to the clearing and faces the terrifying swallowing drum, who asks, ‘Yes fat woman! What do you want!’ Before she can answer, she too is swallowed and the people rush to her asking if she has sharp things. But she first asks to see her daughter and then she shows them the sharp things. The men in the drum stand against the wall of the drum and the women stand on their shoulders. The young boys climb up with the sharp things and begin to chop away at the wooden heart…

When the heart stopped beating, they chopped their way out of the drum, ran back to the village to fetch help and the dangerous swallowing drum was chopped into pieces. The people in that village had good firewood for more than a year.

Resource 2: Sound waves – teacher notes

 Background information / subject knowledge for teacher

What is sound?

Sound is produced whenever an object vibrates. The object could be a string on a guitar, a flat surface such as a drum skin, the diaphragm in a loudspeaker or even the vocal cords.

Sound transfers energy away from the vibrating object, and it needs something to travel through. Sound cannot travel through a vacuum – in space, no one can hear you scream!

Speed of sound

Sound travels at different speeds through different substances. In general, the denser the substance, the faster sound travels through it. Sound travels at 5,100 m/s through steel, 1,480 m/s through water and 330 m/s through air. This is much slower than the speed of light.

Light travels nearly a million times faster through the air than sound does. This is why you hear the thunder clap after you see lightning in a thunderstorm, and why the sound of someone hammering some distance away does not match the hammer blows.

Echoes

Sound can reflect from the surface of an object. This is called an echo. Hard surfaces reflect sound better than soft surfaces.

Loudness

The loudness of a sound depends upon the size of the vibrations. Big vibrations transfer more energy than small vibrations, so they are louder.

Pitch

A sound can range from a high to a low pitch (high to low note). The pitch of a sound depends on how fast the original object is vibrating. If there are lots of vibrations per second, the frequency is high and the sound has a high pitch. If there are few vibrations per second, the frequency is low and the sound has a low pitch.

Checkpoint

The table summarises some features of sound waves and vibrations.

Hearing

We hear because sound waves enter the ear and cause the eardrum to vibrate. Three small bones in the inner ear carry these vibrations to the cochlea (pronounced ‘kok-lee-a’). The cochlea contains tiny hairs, which send messages to the brain when they vibrate.

Resource 3: Ideas pupils may have about working in a group

 Teacher resource for planning or adapting to use with pupils

Choose one of these methods to help your pupils talk about how they worked together in a group.

1. Write each of the following words on to a card, or on the board. Give each group of pupils a set of cards to help them develop three sentences to describe how they worked. They should try to use some of these words in their sentences:

2. Write these statements onto a set of large cards (keep these for different group work activities). Display the statements around the room and ask each group to choose the statements that describe the way they worked.

Encourage your pupils to add further statements.

• Everyone in the group had a chance to speak.
• Everyone in the group was encouraged to speak.
• Not everyone spoke during the activity.
• We reached agreement in our group.
• We listened carefully to each other.
• Sometimes we found it hard to listen to others without interrupting.
• Not everyone in the group agreed with our way of drawing the poster.
• Not everyone in the group contributed to the poster.
• Everyone in the group was able to add to the poster.

3. Choose one or more of these questions. Read it/them out to your class and ask each group to discuss the question(s) in their group for five minutes. Ask for feedback from some of the groups.

• How did sharing your ideas help you?
• Did everyone have a chance to speak?
• Did you encourage each other to share your ideas?
• Did you listen carefully to each other?

Resource 4: Ideas for judging each instrument

 Teacher resource for planning or adapting to use with pupils

These are some questions pupils could ask about each instrument. Brainstorm a list of questions with your class.

What is it made of?

How old is it?

How robust (not easily broken) is it?

Does it need to be kept in a special place?

How easy is it to carry around?

How do you make a sound?

How do you make the note higher? lower?

How do you make a quiet sound? loud sound? Is this easy to do? Can you hear the quiet sound?

What is vibrating?

How easy is it to learn to play?

How much does it cost?

Decide which of these questions are important when judging the instrument. We suggest that pupils in your class choose a maximum of five criteria/questions to judge each instrument.

For each of the five criteria or questions your class has chosen, develop a scoring scale out of 5. The maximum for each instrument would then be 25.

As each group presents their instrument, the class gives them scores for each criterion.

These scores could be recorded on the chalkboard or a large sheet of newsprint on the wall.

Each group should summarise their work by saying:

The final score for our instrument is:

Our instrument is a good choice because … (strengths)

Our instrument might not be a good choice because … (difficulties and problems with the instrument)

Resource 5: Traditional musical instruments

 Background information / subject knowledge for teacher

Nigeria's traditional music uses a number of diverse instruments. Many, such as the xylophone, are an integral part of music across West Africa, while others are imports from the Muslims of the Maghreb, or from Southern or East Africa; other instruments have arrived from Europe or the Americas. Brass instruments and woodwinds were early imports that played a vital role in the development of Nigerian music, while the later importation of electric guitars spurred the popularisation of jùjú music.

Nigerian musical bow

The musical bow is found in Nigeria as a mouth-resonated cord, either plucked or struck. It is most common in the central part of the country, and is associated with agricultural songs and those expressing social concerns.

Cereal stalks bound together and strings supported by two bridges are used to make a kind of raft-zither, played with the thumbs, typically for solo entertainment. The arched harp is found in the eastern part of the country, especially among the Tarok. It usually has five or six strings and pentatonic tuning. A bowl-resonated spike-fiddle with a lizard skin table is used in the northern region; it is an import from North Africa, and is similar to central Asian and Ethiopian forms. The Hausa and Kanuri peoples play a variety of spike-lutes.

Xylophone

The xylophone is a tuned idiophone, common throughout west and central Africa. In Nigeria, they are most common in the southern part of the country, and are of the central African model. Several musicians sometimes simultaneously play a single xylophone. The instruments are usually made of loose wood placed across banana logs. Pit- and box-resonated xylophones are also found.

Adapted from: Africa Alive, Website

Various bells are a common part of royal regalia, and were used in secret societies. They are usually made of iron, or in Islamic orchestras of the north, of bronze. Struck gourds, placed on a cloth and struck with sticks, are a part of women's music, as well as the bòòríí cult dances. Sometimes, especially in the north, gourds are placed upside down in water, with the pitch adjusted by the amount of air underneath. In the south-west, a number of tuned gourds are played while floating in a trough.

Nigerian rattle

Scrapers are common throughout the south. One of the most common types is a notched stick, played by dragging a shell across the stick at various speeds. It is used both as a women's court instrument and by children in teasing games. Among the Yoruba, an iron rod may be used as a replacement for a stick. Rattles made of gourds containing seeds or stones are common, as are net-rattles, in which a string network of beads or shells encloses a gourd. Rattles are typically played in ritual or religious context, predominantly by women.

Adapted from: Aberdeen University, Website

Nigerian Udu drum

Drums of many kinds are the most common type of percussion instrument in Nigeria. They are traditionally made from a single piece of wood or spherical calabashes, but have more recently been made from oil drums. The hourglass drum is the most common shape, although there are also double-headed barrel drums, single-headed drums and conical drums. An unusual percussion instrument is the udu, a kind of vessel drum.

The udu is a Nigerian clay drum that evolved from a water jug with another hole in the side. It was created many years ago by Igbo women who used it as a musical instrument for ceremonial occasions. Udu means both pot and peace in the Ibo language of Nigeria.

Adapted from: Woodbrass, Website

The udu has become a popular instrument in the West and is often used on movie soundtracks. Many modern versions of the udu are being produced today. They have a wider range of tones than the traditional instrument.

Section 3: Investigating electricity

1. Working in groups

It is very important that pupils are given opportunities to think and behave scientifically. This can only happen with practical, hands-on activities. Pupils will be challenged and enjoy working in groups to discuss and discover things for themselves. It often helps their thinking if they use models as well as real items.

Activity 1 uses cut-out shapes to help pupils understand the need for a complete circuit in an electrical device. Case Study 1 shows how one teacher extended this activity and supported her pupils in their own investigations about electric circuits. This type of encouragement and recognition is very important to pupils.

Resource 1: A careful look at the torch bulb shows you how you can extend this work and lead pupils to a clearer understanding that electricity travels in a complete circuit inside a torch bulb.

You may also find it helpful to read Resource 2: Safe ways to investigate electricity, which explains the dangers of electricity but encourages you not to be frightened by the topic.

2. Rotating group work

Electricity provides more than light. Think of the modern electrical appliances we use. We get heat from electricity (stoves, irons, etc.). We get movement (mower, fan etc.). Radios and TVs give us sound. Some pupils may even know that magnetism is also involved in some way with electricity.

You need to think about how you can show these electrical effects to pupils. One way would be to get pupils to be investigators in their local community; they draw up lists of all the effects and uses of electricity that they see around them. Or they could cut out pictures of appliances from adverts in old magazines and newspapers to make a display. Can you think of other ways to make pupils aware of different uses for electricity?

In Activity 2, your pupils move round a number of workstations in your classroom to find out about the effects of electricity; this is an example of rotating group work. You will need to think about how you ask the pupils to record what they have learned in this activity – will they create a poster in each group? Will you ask each group to present their ideas about one workstation? Read Case Study 2 to see how one teacher carried out this activity.

After the activity, ask yourself if your pupils enjoyed this way of working. How could you improve it next time?

3. Planning investigations

The Key Activity builds on the ideas of energy change and the need for complete circuits. In it, pupils work in small groups to explore one effect of electricity – electromagnetism. This type of activity encourages pupils to think about different scientific processes – planning, observing and recording. After the activity, pupils could think of uses for their electromagnets (see Resource 5: Electromagnets for ideas).

Case Study 3 shows how a teacher with very limited resources encouraged her pupils to think through the processes involved in an investigation like this.

Resource 1: A careful look at the torch bulb

 Teacher resource for planning or adapting to use with pupils

First make your teaching aid – a model torch bulb, and read this information about a torch bulb.

With younger pupils, we suggest that you draw in the features of a face to explain what we mean by features.

Now tell them that the class will do the same thing with the torch bulb.

Organise your class into groups of three/four:

Give each group of pupils a torch bulb and ask them to look at it carefully.

• What are the ‘features’ or parts of a bulb?
• Give them a few minutes to observe carefully.
• While they do this, draw the outline of a torch bulb on the board. (Or you can have a ready prepared drawing, which you put up at this point. You can also have labels, written on cards, ready for when they tell you what they observe.)
• When they seem ready, ask them to tell you what they see. You can be open to any suggestions and fill in the picture in a random way. Or you can decide to be systematic and guide their reporting by pointing to a place on the drawing and asking a specific question. As they answer, draw in and label the part – the notes below show you how to do this.

Recording observations in an ordered way Point to the round glass part. What do we see here? Answer: Glass ball What do we see inside the glass ball? Answer: Two thick wires What do we see between the two thick wires? Answer: a thin wire, like a curly hair, called a filament. What do we see between the two thick wires near the base/at the bottom? Answer: A small glass bead What is below the glass bulb? Answer: A metal drum/case/cylinder What can we observe on one side of the metal case, near the top? Answer: A little lump of metal What do we observe right at the bottom of the torch bulb? Answer: A metal/lead tip What do we observe between the metal case and the metal tip? Answer: Black plastic Is there anything else you have observed? Answer: Some may notice writing on the metal case.

Making a teaching aid

You also need to make a large 2-D (flat) model of a torch bulb for the part of the Activity where pupils observe a bulb carefully. You will also use this model when you conclude the Activity.   Cut out the large bulb shape. Cut out the shape for the metal case of the bulb. Glue the bottom of the bulb to the right side rectangle so that it fits over the shaded triangle. Use a large black crayon or koki-pen to draw the thick wires, as shown. Cut out a small oval bead shape from a coloured picture in a magazine and paste it over the black lines you have drawn (this represents the glass bead that prevents the two thick wires from touching). Make the filament from a coil of thin wire, and fasten it across the ends of the thick black lines. One way is to stick the ends of the coil of wire through the cardboard and to use sticky tape on the wrong side (back) to fasten them down. Fold the left-hand side of the base of the bulb over the right-hand side. Now your model of a torch bulb is nearly complete. Use blobs of Prestic to represent the metal solder mark on the side of the case, and the bottom metal tip of the torch bulb. Finally, shade the trapezium shape between the metal case and the metal tip of the torch cell. This shows the layer of black plastic that separates the metal cylinder from the metal tip. This model is specially designed so that you can demonstrate the arrangement of the inner parts of the bulb. What happens inside a light bulb will always be a strange mystery to learners unless they have thought about what might be the case, and then had the chance to find out. It is possible to use a hack-saw blade to carefully cut open the metal case of an old screw-in bulb. Then the arrangement and direction of the wires is clear.

A model light bulb

Now show them the model you have made of the torch bulb. Ask: What do they think they would find, if they could open up the metal case? What would be inside? Where do the two wires go? Give them some time to think.

What do they predict will be the arrangement of wires that are hidden by the metal case?

After a while, you can open up your model and show them how one wire is joined by solder to the metal case, and how the other goes to the metal tip at the bottom of the torch bulb.

Now use your model to demonstrate that there is a complete pathway, or circuit, for the electricity when the bulb lights. The electricity is free to travel in a complete pathway. It travels from the cell, through the wire to the metal case, and then to the one thick wire. From there, it goes through the thin wire filament. It causes the filament to light up, and goes back down the other thick wire to the torch cell again.

Adapted from: Umthamo 3, University of Fort Hare Distance Education Project

Resource 2: Safe ways to investigate electricity

 Background information / subject knowledge for teacher

Two teachers discuss the dangers and safety of electricity with a science advisor and they explain why they are nervous about dealing with electricity in the classroom.

She assures them that the 1.5V batteries and light bulbs that we find in a simple torch are quite safe.

One teacher asks: ‘When is electricity dangerous?’ The specialist explains that the electricity supplied to homes is 220 volts, so it is hundreds of times more powerful than a battery. The high-tension wires that carry electricity across the country are thousands of times more powerful.

So the teachers realised that they could safely conduct electricity experiments in the classroom.

The specialist advised them to make sure that they warned the children of the true dangers of electricity, and she left them some examples of safety pamphlets that are available locally.

The two teachers decided they would also look in the local newspapers for articles about electricity-related accidents and get their pupils to discuss both the causes and the consequences of these tragedies. Here is one example they found:

Eight feared electrocuted in Imo from Charles Ogugbuaja, Owerri

About eight persons are feared dead in a massive electrocution that occurred yesterday in Orji, near Owerri, the ImoState capital.

According to an eyewitness, the accident happened when a small truck carrying a metal kiosk suddenly ran into a high-tension wire. When the kiosk touched the high-tension wire, the many men in the vehicle were electrocuted.

One of them, who was thrown out of the vehicle by the electrocution, died instantly. It is believed that the other men died while receiving treatment.

The public affairs manager of the Power Holding Company Nigeria (PHCN), Owerri district, Mr Osita Ugwuafor, confirmed to The Guardian yesterday that though he was unable to visit the hospital to check the story, he had heard about the deaths of two victims.

‘We are yet to get full details, but [an] unconfirmed source told us that two died earlier. I don't know the state of others because the authorities were yet to allow people to see them,’ he said.

Adapted from: The Guardian, http://www.guardiannewsngr.com/ news/ article17/ 230107 (Accessed 19/06/07)

Resource 3: Lighting a bulb – templates and discussion

 Pupil Use / Teacher resource for planning or adapting to use with pupils

Templates of bulb – for cutting out

Maximise

Templates of batteries for cutting out

Maximise

Discussion notes for Activity 1

Be patient. Let your pupils struggle. Remember that ‘easy come’ knowledge, becomes ‘easy go’ knowledge. Don’t interfere. They will be determined and persist. They may eventually work it out by trial and error. Then they will try to make sense of this and ask: ‘What’s going on here?’

You will see that most young children first think it will light if they just touch the bottom of the torch bulb to the top of the torch cell, metal to metal. They look quite puzzled when it doesn’t work.

They think, ‘No! But it needs some wires! Or a wire!’ Then they link a piece of connecting wire from the base of the cell to the top of the cell. It still doesn’t work.

Watch to see what strategies your pupils adopt.

The bottom of the torch bulb must contact the top of the torch cell, and the wire connects the bottom of the cell to the metal side of the bulb.

The five arrangements

They will probably get these on their own, by trial and error. Give them time and keep encouraging them.

One or two groups may realise that it will still work if the bulb is laid on its side.

Adapted from: Umthamo 3, University of Fort Hare Distance Education Project

Resource 4: Workcards

 Teacher resource for planning or adapting to use with pupils

WORKCARD 1: HEAT

What you have:

• a torch cell/a torch bulb
• a 10 cm length of very very thin, bare wire (unravelled from wire flex from an old broken tape recorder) or fuse wire
• a 10 cm length of ordinary bare copper wire

What you do:

Hold the 10 cm wire with the two ends on the top and bottom of the torch cell. Touch the arc of the wire to the back of someone’s hand. Do they feel anything? Repeat using the length of very very thin wire/or fuse wire. Do they feel anything now? What form of energy do you sense here? Discuss what you have felt. Try to think of an explanation of your own. Experiment using the different wires to light the bulb. Compare the brightness. What do you think?

WORKCARD 2: MAGNETISM

What you have:

• a torch cell
• a 30 cm length of insulated copper wire
• a large soft iron nail
• some metal objects – pins, tacks, etc.
• iron filings
• a small compass

What you do:

First check to see if the large soft iron nail has any effect on the pins, tacks, iron filings and compass. Wrap the wire around the large soft iron nail many times. Hold the two bare ends against the terminals of the torch cell. While it is still attached, check to see the effect on the pins, tacks, etc. What form of energy do you find? Can you get one end of the nail to ‘repel’ (push away) one end of the compass? What is your group’s explanation of what you see here?

WORKCARD 3: MOVEMENT

What you have:

a torch cell

25 cm length of insulated copper wire

a steel needle or pin that has been magnetised (made into a magnet) by being placed alongside a strong magnet for a time

a 15 cm strip of thin, flexible card

a small electric motor from an old broken toy or tape recorder

a drawing pin

What you do:

Make a tight coil by wrapping the wire around a pencil. Fasten the strip of card to the edge of the table/desk so that it is like a swimming pool diving board. Push the magnetised needle so that it hangs vertically from the end of the strip. Hold the coil steady with the magnetised needle dangling into the centre of the coil. Hold the torch cell with one bare end of the wire from the coil in contact with the base. Another person repeatedly touches the other end of the wire to the top of the cell. Discuss what you have seen happen. What form of energy do you find? What is your group’s explanation for what you have seen? Now turn the torch cell upside down and repeat the activity. But first PREDICT what you think you will see. Finally – use the torch cell to work the small electric motor. What direction is it spinning? Can you reverse the direction? Do you think an electric motor might have something to do with coils of insulated wire and magnets?

Resource 5: Electromagnets: Teacher notes

 Background information / subject knowledge for teacher

A magnetic field is produced when an electric current flows through a coil of wire. This is the basis of the electromagnet. We can make an electromagnet stronger by:

• wrapping the coil around an iron core;
• adding more turns to the coil;
• increasing the current flowing through the coil.

The magnetic field around an electromagnet is just the same as the one around a bar magnet. It can, however, be reversed by turning the battery around. Unlike bar magnets, which are permanent, the magnetism of electromagnets can be turned on and off just by closing or opening the switch.

Using electromagnets

Many objects around you contain electromagnets. They are found in electric motors and loudspeakers. Very large and powerful electromagnets are used as lifting magnets in scrapyards to pick up, then drop, old cars and other scrap iron and steel.

Electric bell

Electric bells also contain an electromagnet.

• When the current flows through the circuit, the electromagnet makes a magnetic field.
• The electromagnet attracts the springy metal arm.
• The arm hits the gong, which makes a sound and the circuit is broken.
• The electromagnet is turned off and the springy metal arm moves back.
• The circuit is complete again.
• The cycle repeats as long as the switch is closed.

Original source: http://www.bbc.co.uk/science/ (Accessed 2008)

Section 4: Looking at light and shade

1. Exploring Shadows

Start by investigating light and shade for yourself, using pictures from magazines or photographs. Which parts of the picture stand out because they are directly in the light? Where do you see shade or shadows? Can you work out where the light source is coming from? When do we see a silhouette (the dark outline of an object or person)? Try this out for yourself, perhaps with a colleague.

You are now investigating ‘cause’ and ‘effect’ with regard to light by considering the evidence you have observed and you are thinking scientifically. You might want to try this investigation with some of your pupils.

Case Study 1 shows how it is important for pupils to experience the science they are talking about. In Activity 1, you encourage your pupils to think about effects they observe and to recognise patterns when doing experiments with light.

2. Using games and pictures to explore reflection

Reflection plays a large role in how we see or perceive light and colour. In fact, without reflection, we would see nothing. (See Resource 3: Information on light for more about the properties and behaviour of light.)

In this part, we look at ways you can help your pupils explore what happens when light is reflected off different surfaces. Your aim should not be to provide them with the ‘right’ answers, but to give them a range of experiences that make them thoughtful and interested in this topic. In Activity 2, you encourage your pupils to observe carefully examples of reflection around them. Case Study 2 shows how one teacher’s work on reflection encouraged some pupils to become better artists.

3. Using Science to solve a problem

We try to make sense of our world and then we use what we have found out to help us do things. It is the same with science. Results from investigations can sometimes be used to solve problems we face in life. This is linking science and technology and helps pupils to understand why it is important to study science.

The Key Activity (read this now) builds on knowledge gained from Activity 2 to solve a technological problem. How will you assess your pupils in this activity? After the activity, think about how your pupils reacted to this way of working – did they work well in groups? Would you do anything differently next time you do this?

In Case Study 3, a teacher encourages his pupils to use what they have found out from Activity 1 to plan and present shadow-puppet plays.

Resource 1: Safety advice for teachers

 Background information / subject knowledge for teacher

Not looking at the sun

It is really important that you warn children to NEVER look at the sun directly. Tell them our eyes have built-in lenses that act like magnifying glasses and will focus the HEAT as well as the light energy from the sun onto the tender back of the eyeball, the retina, which helps us see. This heat can burn and destroy forever the cells of the retina, just like a magnifying glass can burn and destroy paper. (Using things like binoculars would be even more dangerous.) Tell them that nobody should ever take chances with something as precious as their sight.

Don’t get burnt

Most other direct light sources also involve quite intense heat. Only insects like fireflies and glowworms seem able to produce light without heat. Supervise children carefully when flames are involved. Also, make sure that matches are kept safe and used properly.

Electric shocks

All the usual necessary precautions need to be taken when electrical appliances are being used in the classroom as sources of light. (No damaged cables, no faulty connections, plugs properly wired, and no water near electricity.)

Finally, it is not nice to think of any pupil getting hurt, burnt or injured, but make sure that you have thought about the possibility that it might happen to you or a colleague, and be prepared to take the proper first aid action.

Resource 2: Wall shadows

 Teacher resource for planning or adapting to use with pupils

Resource 3: Information on light

 Background information / subject knowledge for teacher

Sources of light

• The sun – major source of light and heat here on Earth.
• Stars – distant suns. We can just see the light of these but don’t feel the heat.
• The moon and planets – reflect the light of the sun.
• Lightening flashes during thunderstorms.
• Fire, flames, sparks, heated metals and glowing embers.
• Electric lights.

Colour

• When white light is refracted (bent) by certain transparent surfaces, even raindrops, it is split and reveals the seven colours of the rainbow.
• Coloured things absorb all the other colours but reflect their own colour. So a red car reflects only red light, red glass in a car’s brake light transmits only red light.

Light travels

• Nothing travels faster than light.
• Like sound, light travels as waves of energy. We talk of sound waves, but light ‘rays’ or ‘beams’ of light.
• Light rays generally travel in straight lines that radiate out from a source.
• We see things because light rays bounce off them (get reflected).
• Darkness is because of an absence of light. If there is no source of light to reflect off things we get blackness and cannot see anything.

What happens to travelling light?

• It passes straight through transparent things (glass, water, clear plastic, etc.).
• It partly passes through translucent things (wax paper, tissue, tinted or frosted glass, mist and clouds, etc.).
• Light is blocked by opaque things – this causes shade and shadows.
• Light is also reflected by opaque things.
• Very shiny surfaces (mirrors, polished metal etc.) reflect a clear image/picture.
• Dull surfaces scatter the light that they reflect.
• When light is neither transmitted or reflected, it is absorbed.
• When all the light is absorbed by anything we see it as black.

Mirror images

• When we look into a mirror, the image we see seems to come from behind the mirror.
• A mirror image turns things otherwise (lateral inversion). That is why we can’t easily read a page held up to a mirror.
• Try to shake hands with your own image in a mirror – you will see that as you hold out your right hand, the mirror image ‘holds out’ its apparent left hand

Resource 4: Additional reflection activities

 Teacher resource for planning or adapting to use with pupils

Are we really two-faced?

Are the two halves of our face exactly the same? Pupils might enjoy an activity where you look at full-face passport photographs that they or you bring.

Stand a small hand mirror down the midline of the face in the photograph so that the reflected half makes one face with the uncovered half. Now do the same to the opposite side. Isn’t it amazing how different the two faces are? That is because our faces are not exactly symmetrical.

Shaking the wrong hand

Try to shake hands with your own image in a large mirror – when you hold out your right hand, it offers you its apparent left hand.

Repeat this, but this time, arrange two mirrors at right angles. Look into the corner and you will see one image of yourself. Offer to shake hands.

What hand does the image in the two mirrors offer this time?

Can you work out why this happens?

Using reflection

Brainstorm uses of mirrors:

• Which devices contain mirrors?
• Where are they useful?
• How could mirrors be useful in a shop to help security?

Scary reflections

Experiment with looking at reflections in curved pieces of metal like spoons and kettles.

• What happens to the reflection?
• What patterns can you notice?

Light and dark

Gather together a collection of different shiny materials and objects. Experiment with looking at them:

• in normal classroom light;
• in a ‘black box’ where there is very little light;
• when a torch is shone on them.

Which objects are the shiniest? Can you put them in order of shininess? What happens when you put them in the box? What happens when you shine a torch on them? Can you see any patterns in your observations?

Resource 5: Ideas for creating shadow puppets

 Teacher resource for planning or adapting to use with pupils

Resource 6: Periscopes – ideas to get you started

 Teacher resource for planning or adapting to use with pupils

Start by finding two mirrors.

Hold one in each hand and see if you can use them to peer over a wall or see round a corner.

When you have a good image over the wall or round the corner, stop. Look at how the mirrors are arranged – what do you notice about the angles?

Now you can use your observations to build a periscope. The images below give you some ideas of how to do this.

How will you evaluate your periscope? Are any of these criteria useful? Can you think of any more?

Draw up a table of the criteria you choose and use it to record judgements on everyone’s periscope.

Section 5: From Earth to the stars – using models

1. Using models to explore night and day

Pupils have their own ideas about the difference between night and day based on their experiences. These ideas do not always agree with the scientific understanding. For example, in everyday life, we talk about the sun rising or setting, which implies that it is the sun that moves and not the Earth. However, by using a simple model, it is possible to challenge and extend pupils’ ideas and help them answer the question: ‘Why do we have night and day?’

Activity 1 provides a simple way of modelling night and day and Case Study 1 explores further ideas. You might like to try the activity with your colleagues first, before trying it with pupils. This will test your understanding and help you decide the best way to use the model in your classroom.

2. Using stories and observation to think about the moon

People sometimes refer to the moon when writing or speaking: they use expressions like ‘once in a blue moon’, ‘moonstruck’ and ‘harvest moon’. What expressions do you know that use the word ‘moon’? What expressions do your pupils know? You might make links with literacy work here.

In Activity 2, your pupils observe in detail the shape of the moon over several weeks. You then build on these observations by using everyday objects to model the changes in the moon shape. This will help pupils to understand the pattern in the phases of the moon. Try the model part of the activity yourself before using it with the class.

Using traditional tales about the sun and moon is another way to stimulate pupils’ interest. You could use your own traditional tale instead of the one used in Case Study 2.

3. Representing the solar system

People have always been fascinated by space. Most pupils are interested in space, and the night sky is their first realisation that there is more beyond our world.

Exploring the solar system cannot be done through school visits. But by using books, telescopes, computers, the Internet and models, you can show the vastness and detail of the solar system to your pupils. The size is something pupils find hard to grasp, but making a scale model of the solar system will help.

In Case Study 3, a teacher uses a simulation on the computer, one kind of model, to help develop pupils’ understanding. If you have access to a computer to do this, try the web link listed at the end of Resource 4. The case study shows how the teacher allowed each group of pupils a turn on the computer and the rest of the class worked on a different but related activity.

In the Key Activity, your pupils use models to show the arrangement of the planets. You could extend the model of the solar system by asking pupils to find out how long it takes for each planet to orbit the sun and to turn on its axis (day and night).

Afterwards, reflect on the activity. How did your pupils react to building models? Do you think the models helped them to understand more about the solar system? Could you use models in another topic – what about building models to show particles?

Resource 1: Modelling night and day

 Teacher resource for planning or adapting to use with pupils

Why do we get night and day?

You can use a simple model to help you find out the answer to this question.

You will need:

a large ball to show the Earth

a torch to show the sun

Investigate:

Use the ball and torch to investigate why we get night and day – see below.

Explain how your model shows the difference between night and day.

Adapted from: Oxford Science Programme 2- 1991 Oxford University Press

Resource 2: Day and night questionnaire

 Teacher resource for planning or adapting to use with pupils

What do you think about the statements below?

Score each one according to the following scale. Then discuss your scoring with others.

1. At night, the moon blocks out the sun.
2. The sun revolves around the Earth every 24 hours to give day and night.
3. The atmosphere blocks the sun at night.
4. At night, the planets get in the way of the sun.
5. One half of the Earth has day, while the other half has night.
6. The day and night cycle has something to do with the movement of the Earth.
7. The Earth moves around the sun every 24 hours to give day and night.
8. When we are facing the sun it is day and when we are facing away from the sun it is night.
9. It is dark at night because clouds cover the sun.
10. The Earth spins round once every 24 hours to give day and night.
11. The moon is in a part of the sky where it is always night.
12. The Earth turns around an imaginary line from the North to the South Pole once every day.
13. The Earth spins on a line through the equator once every day.
14. At night, the Earth turns to face the moon.

ANSWERS to Day and night questionnaire

1. False
2. False
3. False
4. False
5. True
6. True
7. False
8. True
9. False
10. True
11. False
12. True
13. False
14. False

Resource 3: Sun, Moon and Water

 Teacher resource for planning or adapting to use with pupils

Maximise

Maximise

Adapted from: Nevin T (1995), Fire’s Wild Dance

Resource 4: The moon and its relationship to the Earth and the sun – background for the teacher

 Background information / subject knowledge for teacher

The moon is a spherical body that is illuminated by the sun and reflects some of its light. But how is the moon placed in relation to the sun and the Earth, and how does it move?

We know that:

Commentary

The diagram on the next page will help you to make sense of how the moon moves around the Earth. It shows how we only see different-sized bits of the moon at different stages in its orbit. It shows how the phases of the moon arise from its orbit around the Earth. The time between occurrences of the same phase (e.g. full) is, on average, 29.5 days.

You will see that the moon always presents the same face to the Earth: the moon rotates on its axis in the same time that it orbits the Earth, and in the same direction. Moreover, whenever you see a full moon, everyone else on the same side of the Earth will also see a full moon. This applies to a new moon and to every other phase of the moon as well.

Please note: You will need to reverse the sequence in the diagram for the southern hemisphere.

Person on earth sees everything inside the circle Moon number 1 = New Moon

Part of the moon in darkness

Part of the moon illuminated by the sun

Useful web link

If you are able to access the Internet, the link below gives your pupils a chance to take part in an interactive tour of the southern hemisphere and has a wonderful animation of moon rotation.

http://www.learningmedia.co.nz/staticactivities/dayandnight/dswmedia/index.html

Adapted from: Primary Science, Developing Subject Knowledge, Jane Devereux

Resource 5: Solar system – facts and figures

 Teacher resource for planning or adapting to use with pupils

Resource 6: A scale model of the solar system

 Teacher resource for planning or adapting to use with pupils

NB: On this scale, our moon would be slightly smaller than a poppy seed and would be 8 cm from the Earth.

All the sizes and distances are approximations.

For practical reasons, you may wish to use this ‘shortened’ distance scale for your pupils’ model, but you will need to point out that the size of the planets is now disproportionately large.