Earth
Earth and Space

Lighting the Earth - Teaching approaches

Classroom Activity for

A Teaching Approach is both a source of advice and an activity that respects both the physics narrative and the teaching and learning issues for a topic.

The following set of resources is not an exhaustive selection, rather it seeks to exemplify. In general there are already many activities available online; you'll want to select from these wisely, and to assemble and evolve your own repertoire that is matched to the needs of your class and the equipment/resources to hand. We hope that the collection here will enable you to think about your own selection process, considering both the physics narrative and the topic-specific teaching and learning issues.

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Selecting and developing activities for lighting the Earth

Earth
Earth and Space

Selecting and developing activities for lighting the Earth

Classroom Activity for 5-11

Suggestions for activities to aid the teaching of 'lighting the Earth' based on the Physics Narrative and the Teaching Guidance.

Ideas to emphasise here

  • The relative location of astronomical objects
  • How the astronomical objects are illuminated
  • That we get information about astronomical objects from seeing
  • That light has to travel from source to our eye so that we can see the source
  • That both spinning and orbiting change what we are able to see

Teacher Tip: Work through the Physics Narratives to find these lines of thinking worked out and then look in the Classroom Activities for some examples of activities.

Strategies for supporting learning

  • Draw on existing models of seeing
  • Make extensive use of well thought out questions to intrigue and to promote fruitful additional questions
  • Relate observations and evidence to assertions
  • Seek to explicitly challenge likely misunderstandings
  • Act out and talk through complex changes

Teacher Tip: These are all related to findings about children's ideas from research. The teaching activities will provide some suggestions. So will colleagues, near and far.

Avoid these

  • Explaining why we see the different phases of the Moon as this draws on a number of different ideas, and is therefore best left until later
  • Explaining why there are different seasons on Earth, as this is complex, and best left until later

Teacher Tip: These difficulties are distilled from: the research findings; the practice of well-connected teachers with expertise; issues intrinsic to representing the physics well.

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A sequence to develop ideas about lighting the Earth

Earth

A sequence to develop ideas about lighting the Earth

Classroom Activity for 5-11

Meeting reality: valuable experiences

The science of astronomy began with observations and it is vital to link this topic to the children can notice more or less directly for themselves. This is important because what we think happens is not always what actually happens and so careful observation often results in surprises. This is particularly true for children who, for example, have been brought up reading story books where the Moon is almost always drawn as a crescent in the night sky. Hence they can be surprised when they observe the various phases of the Moon or see the Moon in the daytime.

In the sciences we observe closely and then step back, think and ask the big questions. Why is it like that? How does that happen?

  • Making careful naked-eye observations
  • Reflecting on those observations
  • Connecting the observations back to the arrangement of the parts and the illumination of the parts
  • Beginning to get a sense of astronomical scales

A sequence for developing the idea

In this topic the main aim is to develop a model that children can use to account for:

  • Day and night
  • The apparent path of the Sun across the sky during the day
  • The movement of the Moon
  • The movement of the planets

The history of the development of human understanding in astronomy is just fascinating. The concept of the Earth being a sphere is not at all intuitive and this was a great step forward in our thinking.

Extending that to realising that the moon was also nearly spherical, with surface imperfections, and again to other planets, again represented huge strides in human understanding.

Teacher Tip: The ideas are developed in the Physics Narrative.

Here you can explore the variation in the length of daylight over the year.

How long is a day?


The Sun is hugely significant for life on Earth, but its perceived movements over the year will very likely need bringing to children attention.

The Sun is a star – a star that illuminates and warms us. The Sun is one star among very, very many. The Sun is, in practice, a huge nuclear reactor, so it does not need oxygen to burn in space – these are nuclear reactions, not chemical reactions. The warming and lighting are powered by these nuclear reactions.

Learning about the Sun


That the Earth is spherical is not an easy thing to believe, and this activity gives an opportunity to explore that idea.

Learning about the Earth


Explaining day and night requires an understanding of the relative movements of the Earth and the Sun, and the consequent changes in the illumination of the Earth. This is tricky, not easily done with diagrams, and is best acted out as in this activity.

Acting out day and night


This activity focuses on the movement of the moon, as seen from Earth.

Learning more about the moon


The focus here is on the movement of the planets, but there is plenty of opportunity for further research work that can intrigue.

Other planets in the solar system


A galaxy is a huge collection of stars. Our Sun is just one star among a hundred thousand million stars that make up the galaxy known as the Milky Way. The Milky Way is a spiral galaxy and the Sun is a star in one of the spiral arms towards the edge of the galaxy. The universe is made up of about a hundred thousand million galaxies – each of which contain about a hundred thousand million stars. This activity seeks to raise some awe and wonder about where we live.

Where we live


Messages from research and practice: specific tripwires for this idea

This topic is all about lighting and relative movement

Whilst this area of science does not lend itself to practical investigations, it is a wonderful one for making links with scientific ideas from the rest of the curriculum, particularly light. There are certain ideas the children need to understand, such as light travelling from a source. We see things around us in the daytime because the light from the Sun reflects off them into our eyes. The Sun looks like flat disc in the sky but, of course, it is a sphere. It will help children to look at a large ball on the other side of the playground to get a feel for the fact that a sphere looks like a plate or disc from a distance. The Sun looks very placid in the sky so it is useful for the children to see some internet photos that show it to be a very dynamic and explosive object.

The Sun appears to move across the sky during the day time and eventually the children will need to understand that it is not in fact the Sun moving around us but us moving around the Sun. It is therefore always best to talk about how the Sun seems to move.

Seeing what is there


Owing to light pollution, we are not as familiar with the night sky as our ancestors. In a city there is so much background light that hardly any stars can be seen at night. It is truly awesome to see the multitude of stars in a clear night sky away from street lights. Many young children will not have experienced this so if they go away with the school and there is an opportunity for them to do this, then they will be amazed.

Teacher Tip: The sciences are all about awe and wonder: don't undersell this facet.

Children find the concept of a spherical Earth very tricky. After all, we have little everyday experience that suggests we live on a sphere.

The shape of the Earth


The concept of the Earth rotating on its own axis is not at all easy. We are living on a sphere spinning around at high speed (about 700 mph in the UK).

Firstly, it does not look like we are moving at all and secondly, it looks just like the Sun moves around us, rather than vice-versa! Big questions are used as a way of helping children think carefully about such things.

The reason we do not have any sense of the motion is linked to relativity – everything local moves with us. We do not have an idea we are moving unless we can see something that isn't or is moving at a different rate. This is why, when we are sitting on a train at a station and the train next to us seems to move, we can't tell if it is our train moving or the neighbouring train. In order to know, we have to look at the platform and if that it still, we are certainly not moving.

Why do we get day and night?


It is very common for children to think that the Moon is only in the sky during the night time.

When is the moon visible?


The immediate space around us seems rather full of plants, houses, people and chairs, amongst other things. So it's rather hard to imagine that the universe is mostly empty. Many diagrams of planetary systems and other astronomical objects

It is mostly space


Why orbiting objects keep orbiting, and don't either stop or just fall down can be an issue. Here it's phrased in terms of artificial satellites, but the same arguments apply to moons orbiting around planets, planets orbiting around stars, or stars orbiting around galactic centres.

What keeps satellites up?


What keeps satellites going?


Teacher Tip: These challenges and some suggestions for working with them are more fully explained in the Teaching and Learning Issues.

Representing and reasoning: doing physics

This sequence is concerned with developing an understanding of day and night, and up the movements of the planets and Moon. it is rather easy to add lots of additional detail, but the focus should be on movement and illumination.

All of the knowledge about the astronomical objects starts with seeing light that is either emitted by, or reflected from these objects. Here the sun is the only luminous object, so the only one that emits light. Other objects, such as the Earth, the Moon, and the planets all are seen by reflected light. All of these objects are in movement, so figuring out where they are and how the light reflects of them is the key to understanding what can be seen.

Lighting moving objects


What's moving: day and night


Both the moon and the planets appear at different locations at different times. Decoding these patterns of appearance into simple patterns of movement took very smart humans several centuries. Here you are just starting to bring children to notice what phenomena there are, and to begin to show how some common pattern can help to make them of these phenomena.

The moon – our nearest neighbour


Movements in the solar system


  • The Sun acts as a source of light
  • The Moon and planets reflect Sunlight, so we can see them
  • What we see depends on where it is, and the source of illumination

Teacher Tip: Find out more from the Physics Narrative.

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How long is a day?

Earth and Space

How long is a day?

Classroom Activity for 5-11

What the Activity is for

How the length of the day varies over the year.

To bring to children's attention to the variation in the length of daylight over the year in a systematic way, and to link this to their everyday activities.

What to Prepare

  • A suitable frame on which to record the data

What Happens During this Activity

A class chart can be made which is completed on the first day of every term/half term, recording what time the Sun rose and set.

Each time this is filled in, using the local times of sunrise and sunset (the Internet, local papers, smart watches, phones etc, are all sources for these times).

The children can then answer the simple questions on the chart:

Teacher: Is it light or dark when you get up in the morning?

Teacher: Is it light or dark when you have your tea?

Teacher: Is it light or dark when you go to bed?

This links the variation of the length of day to their lived-in world, as a rich resource for discussion focusing on the fact that the length of the day varies throughout the year.

You could link this to the weather, which can be recorded and discussed in numerous ways – it is a British pastime! BUt we'd suggest leaving it at noticing patterns, and not to try and explain the seasonal variations.

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Learning about the Sun

Moon
Earth and Space

Learning about the Sun

Classroom Activity for 5-11

What the Activity is for

The children first make observations and then build on these, moving on to think about why these things happen. This is about developing a working model, sometimes known as an explanatory story.

What to Prepare

  • stickers to put on the classroom window

Safety note: Warn the children not to look directly at the Sun because it is so very bright that it will cause damage to their eyes.

What Happens During this Activity

Observing the path of the Sun is most easily done by putting a sticker on the classroom windows to show where the Sun is shining in. This is then repeated at regular intervals throughout the day. The children will see that the Sun appears to move around the sky in the course of a (sunny!) day.

Another way of doing this is to trace the shadow of the netball post on the playground with chalk at hourly intervals throughout the day. If the shadow is carefully, traced, both the direction and length of the shadow will change during the day.

The children could then use a torch and pencil standing upright in a piece of blu-tac to try to model the situation and explain why the shadow changes in the way it does.

Collecting children's questions

We think it's a really good idea to let your children first think what they want to know about the Earth, Sun and Moon. Put out three large pieces of a paper and write either Sun, Earth or Moon on the top of each of them.

Give them time to think about this, perhaps overnight, and then ask the children write any questions they'd like to figure out the answers to on the relevant sheet. Do ask them to put their initials next to their questions – this is a very interesting way of uncovering their existing understanding.

Example of an amazing question from a primary-age child who wrote on the Sun sheet:

Mary: How comes the Sun burns in space if there is no oxygen?

You do not need to worry that you don't know all the answers because you can then can model the pleasure of figuring things out together. However, this one is discussed in the physics narrative!

As the topic continues, the children can tick off the questions as they are answered. Those that remain unanswered at the end can be researched by the children themselves in their own time or left as intriguing questions for the future.

A series of big questions are ideal to really get the children thinking about the Sun. Using the steps of think, pair, share will give them time for deep thinking and also to learn from each other.

Teacher: What shape is the Sun?

Possible answers might be:

  • A yellow circle
  • A big yellow ball

Encourage the children to make links between the Sun looking like a flat disc and the fact that it is a sphere. It may help to look at a big plain yellow beach ball that someone holds up on the other side of the playground. It is a sphere but it looks like a disc in the distance.

Teacher: It is not safe to stare at the Sun in the sky. Why do you think this is?

It is likely that the children will know not to stare at the Sun but this asks them to consider why it is not a good idea. It is important to keep the emphasis on the why?

The Sun's light is so intense that it can damage our eyes. Show them a close-up picture of the Sun (these are freely available on the internet) and ask them to say what they see. They will be able to see how explosive it is and begin to understand that it is a very, very violent place.

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Learning about the Earth

Moon
Earth and Space

Learning about the Earth

Classroom Activity for 5-11

What the Activity is for

We'd suggest that a sequence of questions focusing on the shape of the Earth is the most fruitful approach. The children will have seen globes, so they are likely to know it a sphere.

However, a very big question just has to be asked, which forms the centrepiece of this activity.

Teacher: How do you know the Earth is a sphere?

What to Prepare

  • Stickers to put on the classroom window

What Happens During this Activity

Teacher: So, the big question: What shape is the Earth?

(You might like to rule out pictures from space because they could be forged, and you'd like them to rely on their own senses. You could support this by pointing out that the ancient Greek philosophers had worked out that it is sphere, long before space travel, or even photographs.)

We'd suggest that children think, pair and share so that they have time to think about this carefully.

The children may come up with all sorts of ideas – here are some actual responses from Year 5 children:

Lee: If it's flat, when you make the foundations for a temple why doesn't it go through?

Jenny: Why doesn't water fall off the edge if the Earth is flat?

Azim: Because gravity comes from the centre of the earth, because a sphere is the smallest shape you can make from the centre, it would most likely be pulled up into a sphere.

All these explorations are good but the last one is awesome and shows very advanced thinking, well beyond what you might expect for primary-age children.

Using big questions in this way is an excellent tool for formative assessment.

Convincing evidence

The most convincing evidence is something that they might never have seen:

Teacher: When a bus appears in the distance, the first thing to be seen is always the top of it.

Tell/show them this if needs be (but only after they have a good length of time to come up with their own ideas) and they can then discuss why this observation suggests that the Earth is a sphere.

Counterfactual arguments

Here is a sequence of pictures of a bus coming towards you along a flat road.

Teacher: What would the approaching bus look like if the Earth were flat?

It would look like a tiny toy which just gets bigger and bigger. The fact that the top is always visible first shows that it is coming up over the curve in the Earth's surface.

Ancient thinking

The ancients also observed that the Moon and the Sun appear to be circular and understood that a sphere looks like a disc when seen.

And so they made a connection between a disc shape and a sphere, thinking that the Earth too might be curved.

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Acting out day and night

Moon
Earth and Space

Acting out day and night

Classroom Activity for 5-11

What the Activity is for

Accounting for day and night is quite complex, and we suggest that the very best way for children to develop a helpful understand this is to act out a model of the process.

What to Prepare

  • a simple tabard by laminating two A4 pictures of the Earth, use a hole punch to make 2 holes at the top of each picture, so string can be threaded through and they can hang over a child's neck – one on the front and one on the back.
  • another tabard, similarly, for the Sun
  • another tabard, similarly, for the Moon

What Happens During this Activity

Ask a child to stand in front of the class, wearing the Earth tabard. Tell them that they are the Earth and their nose is the U.K. Shine a torch at them (not too bright a torch!) and then ask them to spin around very slowly. Tell them that the torch represents the light from the Sun. When they are facing away from the torch, tell them to stop and ask the class what time of day it is. The nose of the person being the Earth will not be in the light of the torch so it is dark and night time in the UK. Ask them to spin again until they are directly facing the torch and ask what time of day it is now: midday. Repeat at various points in the spin so they get a feel for evening, as they are about to go out of the light and morning, as they are about to come into the light.

It really helps the children to experience this for themselves. They can pair up with torches and take turns in being the Sun (holding the torch) and being the Earth (spinning).

Children know that day and night last 24 hours so, by acting this out, they will know at a deep level that the Earth spins on its own axis once every 24 hours.

Teacher Tip: You can also model this motion for the class with a globe and a torch but don't let them miss out on acting it out for themselves.

The Earth spins on its own axis as we have discussed but it also goes around (orbits) the Sun.

More acting is needed here: using the tabards again, the Sun stands at the centre and the Earth spins and at the same time travels around the Sun.

The Earth goes around (orbits) the Sun once a year.

Now ask the child being the Earth how they feel. They will be pretty dizzy!

This dizziness can lead on to the next big question.

Connect this dizziness into the observation that as when we look around us, it does not look at all as though we are moving.

Then ask:

Teacher: We have said the Earth is spinning and also going around the Sun, so why don't we sense the motion?

A common answer is that we are not moving very fast but this is not the case at all – the Earth spins around so we are moving at about 700 mph in the UK and, as well as this, it is also orbiting the Sun at a speed of about 66 000 mph.

A Year 5 child quickly came up with this answer:

Lucy: Because everything is moving with us, the trees, houses and everything.

Which is absolutely right – all motion is relative! We do not have an idea we are moving unless we can see something that isn't or is moving at a different rate. This is why, when we are sitting on a train at a station and the train next to us seems to move, we can't tell if it is our train moving or the neighbouring train. In order to know, we have to look at the platform and if that it still, we are certainly not moving. There is more on this is the SPT: Motion and force topic.

Up next

Learning more about the moon

Moon
Earth and Space

Learning more about the moon

Classroom Activity for 5-11

What the Activity is for

More exploration of our nearest neighbour...

What to Prepare

  • A simple tabard by laminating two A4 pictures of the Earth, use a hole punch to make 2 holes at the top of each picture, so string can be threaded through and they can hang over a child's neck – one on the front and one on the back.
  • Another tabard, similarly, for the Sun
  • Another tabard, similarly, for the Moon
  • 2 small spherical beads on a threads suspended from a rod

What Happens During this Activity

It is important for the children to observe the different phases of the Moon and the fact that it too seems to move across the sky in the course of a night. Observations can be made of the Moon's appearance and how this changes over time and also when it can be seen in the sky. This really can only be done as a home project and it can be tricky for children who go to bed early however! It is very good to ask the children what they think.

Teacher: What does the Moon look like?

Give them a night time scene and ask them to draw the Moon in the sky. N.B. Many children's story books have the Moon drawn as a crescent and this is likely to be the most common response.

Teacher: When do we see the Moon in the sky?

Tell the children that scientists do observations and they are going to be Moon spotters – when they see the Moon, they draw its shape and note the time.

Teacher: We know it is not safe to look at the Sun in the sky but it is quite safe to look at the Moon. Why is it safe to look at the Moon?

The Moon is nowhere near as bright as the Sun and this is because it is not itself a source of light. It reflects the light from the Sun. A disco ball seems to shine but it is only reflecting the light falling on it – the ball is not a source of light.

Now the children can act out a slightly expanded model of the solar system with the Earth, Sun and Moon tabards:

Using the tabards again, the Sun stands at the centre and the Earth spins and at the same time travels around the Sun. Now add in the Moon which orbits the Earth whilst it orbits the Sun.

The Moon has the hardest job!

The Moon orbits the Earth once a moonth – a month.

An interesting fact: the Moon always keeps the same side facing the Earth – the other side is the dark side of the Moon. We never see the dark side from Earth and the only people who have seen it are the astronauts who have orbited the Moon. So the child being the Moon keeps his/her face looking at the Earth as they go around it.

The scale of our model of the Earth, Sun and Moon being acted out by the children is a misrepresentation of reality as the scales are wrong.

The best way of getting a feel for the scale is the following demonstration:

Have two small beads hanging by threads from a rod. One bead represents the Earth and the other the Moon. The beads need to be about 10 cm apart so that the scale is roughly correct. Tell the children that we have reduced the Moon and Earth by the same amount and then this is roughly how far apart they would be.

Hold the model up, and ask:

Teacher: Is the Sun larger or smaller than the Moon?

Children tend to know the Sun is bigger. Have a bag with a variety of sized balls in it and bring them out one by one to see which one would be about the right size for the Sun:

  1. golf ball
  2. tennis ball
  3. football
  4. large beach ball

A really large beach ball is about right.

Teacher: How far away does the beach ball need to be for this scale model?

It can be thrown to the middle of the class, back of the class etc. but this would not be far enough: it needs to be 40 m away! It is important to go outside and actually do this.

It is also interesting to ask the children what is between the Earth and the Sun. Admittedly, there are two other planets but these are also relatively tiny and are in constant orbit around the Sun. Children tend to have quite a crowded picture of space and think that there are other stars between us and the Sun. Mostly it is just empty space, no air – nothing at all.

Up next

Other planets in the solar system

Planet
Earth and Space

Other planets in the solar system

Classroom Activity for 5-11

What the Activity is for

Children love to learn about the other planets. The Sun and the planets that orbit around it form the Solar System. The focus here should be on the movements, but there is plenty to engage and intrigue.

What to Prepare

  • A playground
  • Large labels for each planet
  • Another tabard, similarly, for the Moon
  • 2 small spherical beads on a threads suspended from a rod

What Happens During this Activity

Take them out onto the playground and let them be a planetarium and act out the orbits of the different planets around the Sun. Remind them that this is certainly not to scale.

The children can research amazing facts about the planets in our Solar System. If this research precedes the trip to the playground, then the movements should form a focus.

Beyond that, there are many other research lines that could be pursued. Children can then present their findings in any number of creative ways.

One way that works well is to divide the class into groups and give each group one planet to research. They could then present their findings as though they are a foreign correspondent reporting from that planet, telling us what it is like. They could report on the colour of the sky, the number of moons, how long the day lasts and so on. Their reports could be shared in a school assembly; filmed and put on the school website or written up for a class/school newspaper.

Here are a few snippets, to intrigue and stimulate:

Teacher Tip: If a saucepan of water was placed on the surface Mercury then the saucepan would melt!

Teacher Tip: Planets other than the Earth have moons: Jupiter has 16 moons and Saturn has at least 18!More than 1000 Earths could fit inside the giant planet, Jupiter.

Teacher Tip: Saturn is also much larger than the Earth but its day is shorter than an Earth's day because it spins round on its own axis once in less than 11 hours. (Therefore its day lasts just less than 11 hours).

Teacher Tip: A year on Saturn lasts 29.5 times longer than our year because it takes 29.5 times longer to complete its orbit of the Sun.

Up next

Where we live

Earth
Earth and Space

Where we live

Classroom Activity for 5-11

What the Activity is for

It is fun to write the school address on a universal scale, and this can be used to explore some questions about the universe.

Teacher Tip: This goes beyond the remit of the primary curriculum but it is something that just fascinates many children and can be a source of inspiration for them. You'll need to check that the school library has a good selection of astronomy books before setting any research work.

What to Prepare

  • Some address labels
  • Large labels for each planet
  • Another tabard, similarly, for the Moon
  • 2 small spherical beads on a threads suspended from a rod

What Happens During this Activity

Ask the children to write their full address:

xxx School, Street Town, Country, Continent Earth ……… ………

It should go on to include:

Earth Solar System Milky Way Galaxy The Universe

Finally, revisit the beads on threads model used in the previous section about the Moon.

As previously, one bead represents the Earth and the other the Moon. The beads need to be about 10 cm apart so that the scale is roughly correct. On this scale, the Sun is represented by a large beach ball 40 m away.

Hold this model up, with a large beach ball, explaining that it needs to be 40 m away and then ask the children:

Teacher: What is between the Earth and the Sun?

There are two other planets, Mercury and Venus, but these are also relatively tiny and are in constant orbit around the Sun. Children tend to have quite a crowded picture of space and often think that there are a vast number of things, including other stars, between us and the Sun. In reality, there is just about nothing – no air, nothing.

Then ask them to think about all the myriad of stars seen in the night sky.

Teacher: Where, on this scale, would our nearest neighbouring star be found?

Ask for suggestions. They may say in a town 1 km away, or even 30 km away.

Incredibly, on this same scale with the Sun 40 m away from the Earth, the nearest star would be 4000 km away. So if the bead model is held up in a school in the UK, the model Sun is 40 m away on the same scale, and the nearest neighbouring star would need to be in Canada. And we cannot see much between stars. Nor between Galaxies, which are even further apart.

Such is the awesome scale of our universe. What we know about it we learn from the light travelling to our eyes, crossing these huge distances, and travelling for ever such a long time.

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