CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
L earner’s Book
answers
Unit 1 The human body
Topic 1.1: The circulatory system
Getting started
1
Brain
2
Lungs, heart
3
Heart
4
Stomach, intestines
Activity 1: Compare circulatory systems
of some vertebrates
1
Heart, blood, arteries and veins
2
In humans, the blood is pumped from the
heart to the lungs. The blood then goes back
to the heart before it is pumped to the rest of
the body and returns again to the heart. In the
fish, blood is pumped from the heart to the
gills and to the rest of the body before it goes
back to the heart. In the frog, blood flows in
the same pathway as in humans, except that it
also flows to the skin to pick up oxygen before
it flows back to the heart to be pumped to the
rest of the body.
Questions
1
a
The heart pumps blood around the body.
b
To supply all parts of the body with food
and oxygen and to remove waste products
from different parts of the body.
2
The heart muscle contracting as it pumps the
blood.
3
To pick up oxygen that is carried in the blood
to the rest of the body.
4
They each have different jobs to do to ensure
that all parts of the body get food and oxygen,
and that waste products are removed from
different parts of the body. Arteries carry
blood containing oxygen and food to all
parts of the body. Veins carry blood from
different parts of the body back to the heart.
Capillaries join arteries and veins, bring
oxygen and food to the body cells and take
away waste.
5
The heart pumps blood in arteries to the lungs
to pick up oxygen. The oxygen-rich blood
travels back in veins to the heart. The heart
pumps the oxygen-rich blood in other arteries
to the rest of the body. The blood from the
rest of the body, which is now low in oxygen,
travels back to the heart in veins.
Think like a scientist 1: Measuring
pulse rate
Steps
1–4 Answers will vary. Normal pulse rate in
children is about 90 beats per minute.
The number of heartbeats counted will
probably vary slightly when the pulse is
taken again.
Learners’ tables should record pulse rates
(in beats per minute) of group members.
Questions
1
Heartbeat is the contraction of the heart
muscle as it pumps blood. Pulse is caused by
the pressure of the blood as it is pumped by
the heart.
2
No. Learners may not have measured their
pulse rates accurately. Some people may be
fitter than others and have lower pulse rates.
Accept any other reasonable answers.
3
Learners should add the measured pulse rates
together. They should then divide the total by
the number of measurements taken.
4
Observing over time
lungs
heart
body
1
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Think like a scientist 2: How does
exercise affect pulse rate?
Think like a scientist 3: Ask and
investigate a question
Steps
1 a Exercise will increase the pulse rate.
Learners should be able to predict from
their own knowledge and experience that
our pulse rates increase when we exercise.
Some learners may be able to explain that
our bodies need more oxygen when we
are active, which means the heart has to
pump faster to supply the extra oxygen.
As a result, the pulse rate increases.
Learners could ask questions about the circulatory
system as a whole, about the heart, about blood
vessels or about blood. These are some possible
questions:
• Do different animals have different
heartbeat rates?
• Does body size affect heartbeat rates?
• How do different kinds of exercise affect
pulse rates?
• How long does it take for a person’s pulse rate
to return to normal after exercise?
b
2
Measure pulse rate before and after
exercise.
Variable to measure – pulse rate.
Variable to change – amount of exercise/body
activity.
Variables to keep the same – the method and
equipment used to measure pulse rate, the
person whose pulse rate is measured.
3 Timer, stopwatch or watch with second hand
4&5
Results can be recorded in a table and
presented in a bar graph.
Questions
1
Answers will depend on the prediction made.
2
Pulse rate increased when the person
exercised.
3
Exercise makes the pulse rate increase.
4
Fair testing and observing over time. In the
fair test we measured a change in one variable
(pulse rate) when we changed another variable
(the amount of exercise the person did). We
kept other variables the same. The changes
were measured over a period of time, e.g.
every two minutes.
Activity 2: Identify other factors that
affect pulse rate
Learners should use secondary information
sources, such as books, the internet or videos to
find answers to the questions about pulse rates.
Learners’ research should show that pulse rates
can also vary according to fitness, age, gender and
time of day, as well as emotions. For example, our
hearts beat faster when we are nervous. Fit people
generally have lower pulse rates than unfit people.
Males usually have lower pulse rates than females.
Young children usually have higher pulse rates
than adults.
2
Depending on the question learners ask, they could
choose various methods of scientific enquiry to find
the answer: for example, fair testing, pattern seeking
or research. Tell learners to look at the pages on
Scientific Enquiry skills at the beginning of the
Learner’s Book to help them decide which type of
scientific enquiry would be most suitable for finding
the answer to their questions.
Learners could share what they have found out in
various ways, such as through a class question and
answer session or writing a fact sheet.
Topic 1.2: The respiratory system
Getting started
Learners’ answers will depend on their prior
knowledge and understanding about the lungs.
Use their answers to identify and address any
misconceptions.
Activity 1: Investigate breathing
2&3
4
Learners will feel their rib cage
expanding and moving outwards when
they breathe in.
Learners will feel their rib cage
contracting and moving inwards when
they breathe out.
The balloon inflates as it fills with air. This
shows that air leaves our bodies when we
breathe out.
Questions
1
The chest gets bigger because the lungs fill
with air.
2
The chest gets smaller because the lungs push
air out.
3
Air leaves our body when we breathe out.
The air fills the balloon and the balloon
inflates/becomes blown up.
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Steps
6 a & b When you pull the bottom balloon
down, the balloon inside the bottle
inflates. When you let go, the balloon
inside the bottle deflates.
Questions
1
a
b
c
d
Balloon inside the bottle
The bottle
The straw
The balloon around the cut-off base of
the bottle
6
Graph is based on sample results table.
Graph of breathing rate
Number of breaths per minute
Think like a scientist 1: Make a model
to explain breathing
35
a
Before exercise started
30
25
20
15
10
5
0
0
2
4
6
Time in minutes
8
2
The ribs
b
3
When you pull down on the balloon
diaphragm, air is pulled into the bottle. This
makes the balloon inside the bottle inflate as it
fills with air. This shows breathing in.
When you let go, the balloon diaphragm moves
upwards and air is pushed out of the balloon
inside the bottle. This shows breathing out.
Exercise made the breathing rate increase.
You need more oxygen when exercising,
so you have to breathe more often to get
enough oxygen into the body.
c
Learners’ own answers. In the sample
graph it would take about 5 minutes after
exercise stopped for the breathing rate to
get back to normal.
4
The model lung is hollow and not spongy like
a real lung.
7
Exercise makes the breathing rate increase (or
similar conclusion).
Activity 2: Find out how other animals
get oxygen
8
How fit a person is
9
Observing over time
Learners should find out that other animals have
different respiratory systems for obtaining oxygen.
Simple animals such as worms obtain oxygen by
absorbing it through their skins. Insects have openings
on their bodies called spiracles through which oxygen
enters and carbon dioxide leaves the body. Fish do
not have lungs, but have gills that absorb oxygen
from the water. Other vertebrate groups (amphibians,
reptiles, birds and mammals) have lungs and display
breathing movements, although amphibians also
absorb some oxygen through their skins.
10 Circulatory system
Topic 1.3: The reproductive
system
Getting started
1
Reproduction is the process by which living
things produce more of their own kind/have
young (or similar answer).
2
To replace individuals that get old and die/so
that all the different kinds of living things do
not die out when the adults get old and die (or
similar answer).
3
a
Most learners should identify themselves
as being in the ‘child’ stage (at the right),
but some may consider themselves to be
in the ‘young person’ stage.
b
Answers will vary. Parent will be in the
‘adult’ stage. Learners may have siblings
who are younger or older than themselves
and may be in different stages in the life
cycle.
Think like a scientist 2: Investigate
breathing rate
1–4 This is a table of possible results.
Time (minutes)
0
2
4
6
8
Breathing rate (breaths
per minute)
15
20
30
25
17
Exercise starts at 0 and ends at 4 minutes.
3
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Activity: What do you know or want to
know about puberty?
1
Puberty is the stage in which your body
changes and develops so that you are able
to become a parent/reproduce (or similar
answer).
2
Answers will depend on whether the learner is
a girl or a boy.
Before puberty
Boy and girls
normal growth in
height
little body hair
skin not oily
Boys
voice not deep
narrow shoulders
and chest
Girls
narrow hips
no breasts
3
Changes during puberty
fast growth in height
more body hair grows
skin may get oily
voice gets deeper
shoulders and chest get
broader
hips widen
breasts start to develop
Learners’ questions are confidential.
2
Types of living
things
bacteria
viruses
fungi
other parasites
Activity 1: Find information about
diseases
Answers should include the following information:
The word we use to describe any living thing that
causes a disease is pathogen.
The names of the parasites that cause malaria
and yellow fever are Plasmodium (malaria) and
Entamoeba (dysentery).
Malaria is spread by mosquito bites; dysentery is
spread by contaminated food and water.
Activity 2: Group methods to prevent
diseases
How disease
is spread
In food
Methods to prevent spread of
disease
Wash your hands with soap and
water.
Do not leave food at room
temperature.
Keep the kitchen, toilet and
surroundings clean.
Wash raw unpeeled fruits and
vegetable before eating them.
Keep food covered.
Wash knives and working
surfaces in the kitchen with hot
soapy water after using them.
In water
Only drink safe, clean water. Boil
water from rivers or reservoirs, or
treat it with bleach to kill germs.
Do not use rivers or other bodies
of water as a toilet.
Cover your nose and mouth
when you cough or sneeze.
Keep wounds covered with a
plaster and do not touch other
people’s open wounds.
Questions
1
To make sex cells
2
a
Sperm
b
Ova or eggs
3
a
Testes
b
Sperm duct
4
a
Ovaries
b
Oviduct
c
Uterus
d
Birth canal
c
Penis
Topic 1.4: Diseases
Getting started
1&2
3
Answers will depend on learners’ own
experiences.
An infectious disease is a disease that is caused
by very small living things called germs.
Questions
1
4
a
Any living thing that lives on or in the
body of another living thing.
b
They grow and reproduce in the bodies of
other living things.
Examples of diseases
they cause
cholera, pneumonia
flu, chicken pox
ringworm, athlete’s foot
malaria, dysentery
In body
fluids
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Think like a scientist: Analyse hygiene
methods that people use
2
Both the ancient Chinese medical book
and Malpighi had the idea that the blood
circulated through the body in a continuous
pathway. Malpighi suggested that the
capillaries connected the arteries and veins
to allow the continuous blood circulation to
happen.
3
He observed water pumps (in London).
4
a
He studied the heart and blood vessels
and carried out experiments.
b
To make sure that his observations and
results were reliable and correct.
a
He observed that in one hour the heart
pumps more than the body’s weight in
blood.
1
wash
hands
after
toilet
2
wash
hands
before
working
with
food
wash
keep
cover
hands
kitchen,
nose
after
toilet
and
working
and
mouth
with
surroundings
when
food
clean
coughing
or sneezing
a
Keep the kitchen, toilet and surroundings
clean.
b
Wash hands after working with food.
3
The soap helps to kill germs.
4
So that they don’t spread germs from their
hands to the food they are going to work with,
and so that they don’t spread germs that might
already be on the food they work with.
5
To stop germs from our bodies spreading
through the air to other people.
6
Germs live and grow better in moist
conditions; a dirty towel may have germs on it
which rub off onto our hands.
Project: The circulatory system
Part 1 Discovery of how the circulatory system
works
1
a
b
5
They incorrectly thought that:
• the liver produced blood
• the lungs moved the blood around
the body
• the body used up the blood for energy
as it flowed to the different organs
• the heart’s function was to control
our feelings
• blood could pass directly from the right
side of the heart to the left side of the
heart through small holes
• arteries contain air.
They correctly thought that:
• there are arteries and veins in the
circulatory system
• blood moves from the right side of the
heart to the lungs and back to the left
side of the heart
• arteries contain blood.
5
b
The heart works by muscle contraction to
pump blood to body organs.
Blood is carried away from heart by
arteries and returns to the heart through
veins.
Gases enter and leave the blood in the
lungs.
Part 2 Draw a timeline of discoveries about the
circulatory system
Learners should work in pairs to draw their
timelines.
They should find the following answers to the
research questions:
• Transplanted the first human heart: Christiaan
Barnard, 1967.
• Discovered that humans can have different
blood types: Karl Landsteiner, 1901.
• Invented the first stethoscope to listen to the
heart beating: René Laennec, about 1816.
• Discovered that a substance in the blood
called haemoglobin carries oxygen: Frederick
Hunefeld, 1840.
Learners should display their timelines in the
classroom.
Check your progress
1
a
b
c
d
e
False – the heart pumps blood around the
body
True
False – your pulse rate tells you how fast
your heart is beating
True
False – arteries carry blood to all parts of
the body OR veins carry blood from all
parts of the body to the heart.
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2
a
Timer, stopwatch or watch with a second
hand
b
B = before exercise
A = after exercise
130
Topic 2.1: Proprties of substances
120
Pulse rate in beats per minute
Unit 2 Materials:
properties and changes
110
Getting started
100
Use learners’ own answers to identify any errors or
misconceptions they may have about changes of
state.
90
80
70
Activity: Compare boiling and
evaporation
60
50
1
40
30
20
10
0
B A
Marcus
B A
Arun
B A
Jamal
B A
Kai
Name
3
4
5
c
Exercise makes their pulse rates increase.
d
Their pulse rates would be lower than they
were directly after exercise. Our bodies
need less oxygen when we are at rest so
the heart will beat slower and the pulse
rates will decrease.
a
Lungs
b Oxygen
c
Carbon dioxide
d Blood
e
Diaphragm
f Ribs
a
Puberty is the age at which a person
becomes able to reproduce.
b
Any two from grow taller quickly, develop
more body hair, skin becomes more oily
Tears – contain a chemical substance that
kills some bacteria
Mucus – traps germs
Stomach acid – kills bacteria in food we
have eaten
Skin – stops bacteria entering the body
6
Bubbles form in the liquid.
b
The volume of liquid decreases/there is
less liquid in the container.
c
Boiling – heat is added to make the liquid
boil, so the particles gain energy more
quickly than in an unheated liquid. This
makes the liquid particles change to a gas
faster.
Look for similar drawings in learners’ answers.
evaporation
boiling
gas
particles
bubbles
a
b
2
a
The skin is a barrier that stops germs
from entering the body. If we get a cut or
wound, we must clean it to remove germs
from the wound. We must cover it with
a plaster to stop any germs from getting
into the body through the broken skin.
Think like a scientist 1: Measure and
compare melting points
Questions
1 a & b These are melting points for the
substances suggested.
Ice – 0 °C
Butter – 35 °C
Candle wax – 57 °C
Beeswax – 63 °C
Soap – 55 °C
Coconut oil – 25 °C
Answers will depend on the
substances chosen.
2
Learners’ own bar charts.
3
Different substances have different
melting points.
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4
5
No. The melting point is a property of the
substance and will stay the same no matter
how much of the substance is used. The time
taken for melting will increase if more of the
substance is heated.
Because less heat energy is needed to change
a solid to a liquid than to change all the
particles in a liquid to a gas.
Think like a scientist 2: Plan a test to
compare boiling points of substances
1
Variable that changes is the substance tested.
Variables that stay the same are the
thermometer used and the method used to test
each substance.
Variable that is measured is the temperature at
which the substance boils.
2
Learners will need:
• a variety of liquids, e.g. water, vinegar, fruit
juice, milk, cooking oil
• a gas burner or hot plate and a thermometer
• beakers or pans.
3
Heat each liquid in a beaker or pan until it
boils. Measure and record the temperature of
the boiling liquid in each beaker or pan.
4
Getting burned is a risk. Don’t touch the
burner/hot plate or the hot beaker or pan.
Wear protective gloves and goggles.
5
Record readings in a table. Present results in a
bar graph.
Topic 2.2: Thermal and electrical
conductors
Getting started
1
Heat energy from the hot water is transferred
to the metal teaspoon and then to your hand
when you touch the teaspoon.
2
Hot water → teaspoon → hand/person
Think like a scientist 1: Investigate how
well different materials conduct heat
Questions
1
Learners’ own answers. Answer should be the
bead on the metal spoon because metals are
good thermal conductors.
2
Order should be: metal spoon, glass rod,
plastic spoon, wooden pencil, polystyrene
3
a
b
The bead on the metal spoon
Answers will depend on learners’
predictions.
4
a
b
The bead on the polystyrene
It is not a good conductor of heat.
5
Metals are good conductors of heat.
Non-metals (glass, plastic, wood and
polystyrene) are not such good conductors
of heat.
6
Measure the time it takes each bead to fall off
and use the results to draw a bar graph.
7
Observing over time and fair testing. Learners
observed the time it took for the bead to fall
off each spoon. It was a fair test because the
only variable that was changed was the material
that the spoons were made from (independent
variable). The dependent variable measured
was the time taken for the bead to fall off
each spoon. The control variables were the
water temperature and the size of the bit of
petroleum jelly and the bead on each spoon.
Think like a scientist 3: Investigate the
properties of gases
Learners’ drawings should show that the ruler
tilted and became unbalanced when air was let out
of one of the balloons.
Questions
1
The balloons filled up and expanded as air
was blown into them.
2
The balloon that remained full of air caused
the ruler to tip as it was heavier than the
empty balloon. This shows that the air has
mass. The empty balloon’s air escaped into
the surrounding room and was no longer
contained within the balloon.
3
7
We wore safety goggles as protection in case a
balloon burst; used scissors carefully so as not
to get cut; handled heavy books carefully.
Questions
1
A thermal conductor is a material or
substance that allows heat to pass through it
easily (or similar answer).
2
Metals are good conductors of heat, so the
heat from the stove passes easily through the
metal to the food in the pot or pan.
3
Plastic is not a good conductor of heat, so the
heat from the hot pot or pan does not pass
easily to your hand when you hold the handle.
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5
A polystyrene foam cup. It is a poor thermal
conductors, so the heat from the tea cannot
be transferred easily from the cup into the
surroundings.
2 and 6a
Substance
copper
steel
aluminium
water
sugar
graphite
Prediction: How
brightly I think
the lamp will
shine?
Observation:
How brightly did
the lamp shine?
✓✓
learners’ own
prediction
learners’ own
prediction
learners’ own
prediction
learners’ own
prediction
learners’ own
prediction
✓✓
✓
✓
✓
copper
b
it is bright (2 ticks)
4
a
not very bright (1 tick)
6
b
To make sure that their results are more
reliable, learners could repeat the test.
They could also compare their results
with those of other groups. If the results
are similar, they are more likely to be
reliable.
Questions
1
Answers will depend on learners’ predictions.
2
Copper, steel and aluminium
3
a
Copper
b
Sugar
4
Metals are good electrical conductors/Nonmetals are poor electrical conductors.
5
Substances that conduct electricity: copper,
steel, aluminium, graphite, water.
Substance that does not conduct
electricity: sugar
8
Identifying and classifying
Scatter graph of values for conduction of heat and electricity
70
copper
60
50
aluminium
40
30
unknown
20
steel
10
0
brass
graphite
0
50
100 150 200 250 300 350 400 450
Heat conduction
2
a
c
3
The substances that conduct heat well are also
good conductors of electricity.
4
The measurements for graphite do not fit
the pattern. Graphite is a poor conductor of
electricity, but it conducts heat quite well.
5
Accept any value for electricity conduction
between 100 and 130.
6
A substance that conducts heat well also
conducts electricity well OR Metals are good
conductors of electricity and heat OR The
better a substance conducts heat, the better it
conducts electricity.
✓
a
6
1
Thermal insulators
Think like a scientist 2: Investigate
how well different substances conduct
electricity
3
Activity: Compare thermal and
electrical conductors
Electrcity conduction
4
Copper
Steel
b
d
Copper
Graphite
Topic 2.3: Reversible changes
Getting started
1
a
The ice has started to melt.
b
Drawings should show the ice cube melting.
2
Heat causes the ice to melt because it makes
the particles in the ice move faster and further
apart until they have enough energy to become
a liquid.
3
If we put the melted ice back in the freezer
it will become solid ice again because it loses
heat energy. As the particles in the liquid lose
heat energy, they slow down and move closer
together until they form a solid.
Questions
1
We can make solid jelly become liquid by
heating it.
heating
Solid jelly
liquid jelly
cooling
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2
An irreversible change. The liquid egg white
and yolk become solid and cannot be changed
back to liquids.
Think like a scientist 1: Demonstrate a
reversible change
1
Learners can choose any change of state:
melting, solidifying/freezing, condensation,
evaporation. They could also choose
dissolving.
2
a
Answers will depend on which reversible
change learners choose.
b
If learners are heating substances, they
should take care not to burn themselves.
3&4
Questions
1
How fast a substance dissolves
2
Stirring and temperature
3
a
Heating makes the particles of the solvent
move faster and spread out more. When
the solute is added to the heated solvent,
the solute particles also gain heat energy
and move faster.
b
The solute particles spread out and move
more quickly into the spaces between the
solvent particles. This makes the solute
dissolve faster.
4
Materials, equipment and answers will
depend on which reversible change
learners choose to demonstrate.
Activity: Describe dissolving
1
The copper sulfate – I can see it spreading out
in the water.
Think like a scientist 3: Ask and
investigate a question about dissolving
2
The water
3
Learners’ drawings should show a uniform
blue solution.
4
Learners should explain that the solute
particles move and spread out between the
solvent particles until they are evenly spread.
5
Dissolving is a reversible change. We can get back
the solute by evaporating the solvent. We can
change the evaporated solvent back into a liquid
by allowing it to condense on a cooler surface.
In this activity, learners should think of their own
question about dissolving that they would like to
find the answer to. These are some possible ideas:
• How much solute can dissolve in water at
different temperatures?
• Does the type of substance affect how fast it
dissolves?
• Do all solids dissolve faster when we heat the
solvent?
• Are there any other factors that can affect the
rate of dissolving?
a
Learners should observe that the sugar
dissolves more quickly in the jar of hot
water. The hot water makes the particles
move faster so the solute and the solvent
particles come into contact with each
more quickly.
Learners should choose the appropriate type of
scientific enquiry to answer their question. Tell
them to look at the ‘Working like a scientist’ pages
at the beginning of the Learner’s Book to remind
themselves of the features of the different types
of scientific enquiry. Answers and methods of
investigation used will depend on the questions
that learners ask. They could present their findings
in a poster or using presentation software, such as
Microsoft Powerpoint.
b
Answers will depend on prediction made.
Topic 2.4: Chemical reactions
Think like a scientist 2: Does water
temperature affect the rate of
dissolving?
1
2
3
9
The sugar will eventually dissolve because the
movement of the water particles and sugar
particles will bring enough of them into contact
with one another, so that the sugar particles can
spread out between the water particles without
stirring or heating the solution.
The same amount of solute and solvent were
used in each test, only the water temperature
was changed. Learners should also have stirred
both solutions the same number of times.
Learners should conclude that a solute
dissolves faster in hot water or that heat makes
a solute dissolve faster.
Getting started
1
The candle wax melts. It is heated which
makes it change from a solid to a liquid.
2
The candle wick burns/becomes black. This is
not reversible.
3
A new black substance (soot) formed on the
back of the spoon; smoke also forms.
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Check your progress
Think like a scientist 1: Identify
reactants and products
2
b
3
The bicarbonate of soda and vinegar reacted
together to make a gas (or similar explanation).
4
The bicarbonate of soda and vinegar
5
The gas
Learners’ drawings should show gas
bubbles coming out of the jar.
1
6 a & b After a few minutes, a white substance
forms in the jar.
Think like a scientist 2: Investigate
evidence for chemical reactions A
1
2
d
2
Learners’ drawings should show a colour
change of the iodine from yellow-brown
to blue-black.
b
Carbon dioxide
c
Learners should describe the change in
the colour of limewater from clear to
milky white.
3
The change in colour is evidence that a
chemical reaction has taken place.
Investigate evidence for chemical
reactions B
a
The temperature at which a solid melts
and becomes a liquid.
b
Copper, gold, silver, aluminium, candle
wax, ice
c
The metals have much higher melting
points than the substances that are not
metals.
d
No. A melting point is a property of a
substance, so each substance has its own
melting point that does not change.
a
Metals conduct heat better than nonmetals like glass. This means that the heat
from the oven is transferred more quickly
to the food in the metal dish.
b
Yes. How well a substance conducts heat
is a property of a substance, so a different
metal will either conduct the heat better
or worse than the first metal dish.
3 a & b Reversible processes: boiling, freezing,
evaporating, dissolving + melting or
condensing; Irreversible processes:
rusting, burning + cooking, baking,
rotting or other suitable answers.
4
2–5
Learners should observe an increase in
temperature and rusting of the wire wool.
a
In hot water
b
Adding heat makes the particles of the
solid and the water move faster and
spread out more. This allows the particles
of the solid to move between the water
particles more easily, so the solid dissolves
faster.
a
The iron nail changed colour.
b
Iron, air and water
c
The chemical name for rust is iron oxide.
The should conclude that a change in colour and
temperature are evidence that a chemical reaction
has taken place.
5
Questions
1
2
3
10
A gas is produced, e.g. vinegar and
bicarbonate of soda react to produce a gas.
There is a colour change, e.g. when iodine reacts
with starch and changes from yellow-brown to a
blue-black colour or when clear limewater reacts
with carbon dioxide and turns white.
There is change in temperature, such as in
a reaction between wire wool and vinegar;
washing powder and water; cement and water.
Unit 3 Rocks, the rock
cycle and soil
Topic 3.1: Igneous rocks
a
Limewater and carbon dioxide
Getting started
b
Calcium carbonate
1
c
The colour of the limewater changes from
clear to milky white.
A: Earth’s crust, B: mantle, C: outer core,
D: inner core
2
Magma
3
A volcanic eruption occurs.
Bubbles of gas form.
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Think like a scientist 1: Collect and
sort rocks
Learners’ answers will vary according to the rocks
they collect and study.
Activity 1: Use text, a photograph and
a diagram to describe how sedimentary
rocks form
1
Any one from heating and cooling of rock to
break up surface layers; plant roots breaking
up surface rock and rain loosening and
dissolving rock.
2
The river uses the broken rocks to scrape the
sides and bottom of its valley.
3
On the sea bed or lake bed
4
Because the rocks are formed of layers
5
Weathering; eroding; transporting; depositing;
sedimentation
Activity: Describe igneous rocks and
complete a key
1
Solidification
2
Slowly, because the crystals are large enough
to see with the naked eye.
3
Intrusive igneous rock
4
Quickly, because the crystals are too small to
see with the naked eye.
5
Extrusive igneous rock
6
a
b
c
7
Quartz
White and larger than the other crystals.
Mica
Missing words: Left granite; right extrusive
Think like a scientist 2: Make your
own crystals
Questions
1
a
b
2
3
The risk is pouring the hot water into
the jars.
Use protective gloves while pouring the
hot water.
Learner’s own response. Best reasoned
prediction is that jar 1 in the cool environment
will start to make crystals first.
Learner’s own response. Best reasoned
prediction is that the bigger crystals will be
in jar 2 which is in a warm place so will cool
down more slowly.
4
Learners’ own responses
5
The warmer the environment, the bigger
the crystal.
6
The warmer the environment, the slower the
crystal forms (or the cooler the environment,
the quicker the crystal forms).
7
Jar 2.
Topic 3.2: Sedimentary rocks
and fossils
Activity 2: Identify and describe
sedimentary rocks
1–3
Learners’ own responses
4
Sedimentary rocks are formed of sediments
stuck together.
Sedimentary rocks form in layers.
5
Missing words
Left – sandstone
Middle – shale
Right – limestone
Think like a scientist: Make your own
plant fossil
1
2
a
Sediments on the sea bed
b
Minerals
Because sedimentary rocks form in a sea or
lake where the animals’ dead bodies lie.
Topic 3.3: Metamorphic rocks and
the rock cycle
Getting started
1
The rocks are shiny, crystalline and of different
colours: white, brown, blue and yellow.
2
Some learners might recognise that this is
marble. You can tell them that the rock is
marble and that the rock used to be limestone
before it was changed or metamorphosed into
marble – that’s what we will be finding out in
this topic.
Getting started
The rocks are different to igneous rocks because
they are a reddish-brown in colour (not shiny or
crystalline) and they are formed of layers.
11
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
To be able to carve this rock and make these
patterns which have lasted for hundreds of years,
it must be possible to cut and carve the rock, so it
must be hard but not crack and shatter when you
hit it.
Activity 1: Identify and describe
metamorphic rocks
Getting started
1
Soil
2
Rocks
3
Weathering is the process where rocks are
broken up by heat and cold, rain and ice.
1
Marble
2
Sandstone
3
It changes into slate.
4
Gneiss is a metamorphic rock that forms when
granite is changed by heat and pressure.
5
Learners’ own responses
Activity 1: Types of soil
6
Metamorphic rocks are shiny because they are
crystalline.
Metamorphic rocks sometimes have many
layers because of pressure.
Metamorphic rocks sometimes have bands of
crystals because of pressure.
1
Think like a scientist: Investigate a
soil sample
Think like a scientist: How people use
rocks in my area
Learners’ answers will depend on the examples
they find.
Activity 2: Describe how a model can
help us understand the rock cycle
1
Because it shows how rocks are continuously
formed, broken down and re-formed.
2
Arrows
3
Weathering and erosion
4
Cooling
5
Melting
6
Heating, pressurising and burial
7
It can be buried, heated and put under
pressure and changed into metamorphic rock.
Or it can be weathered and eroded to make
sediments which become new sedimentary
rock.
8
1–7 and 9–10 Learners’ own responses
8
Air
Learners’ own responses
2
Size of particles
Sandy
soil
Large
Quantity of
A little
water soil holds
Size of air spaces Large
Quantity of
Small
organic matter
3
Clay soil Loam
Small
A lot
Large
and
small
Medium
Small
Small
Medium
Large
Clay soil, because it holds a lot of water and
the water cannot drain through it.
Activity 2: Changing the composition
of soil
1
2
a
Water the soil when there is no rain.
b
Dig in compost or fertilisers.
c
Dig the soil and add sand.
a
Loam; the dark brown colour shows that
it contains a lot of organic matter.
b
She mixes air and organic matter in with
the soil by turning it with a hoe.
She takes out the weeds.
She waters it in dry weather.
a, b and c
sedimentary rock
granite
magma
12
Topic 3.4: Soil
burial, heat and pressure
heat and pressure
cooling
metamorphic rock
gneiss
granite
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
3
Action
Change in the
composition of the soil
Planting same
Plant uses up all
plant on same soil nutrients in soil. Soil
over and over again becomes dry.
Using artificial
Damages soil texture.
fertilisers
Dries out soil.
Using pesticides
Kills organic matter
in soil.
Not digging and
Air and organic matter
turning soil
not mixed in the soil.
2
a
b
A consumer is a living thing that cannot
make its own food and must eat other
living things to obtain its energy.
herbivores
zebra
locust
sheep
omnivores
monkey
bear
carnivores
tiger
heron
crocodile
Check your progress
1
1E; 2A; 3C; 4B; 5F; 6D
2
a
Basalt
3
a
Igneous
b
It is crystalline
c
Minerals (or crystals of minerals)
d
Magma inside the Earth’s crust cooled to
form solid rock.
Think like a scientist: Explain a food
web and draw food chains
a
Sedimentary
1
b
4
5
6
b
Limestone
c
Loam
Corn → mouse → snake
2
Cabbage → snail → duck → fox
3
Pond weed → tadpole → fish → person
Palm shoot, fig, jack fruit
It contains fossils
b
Spotted deer, coconut palm beetle, fruit bat
c
On the sea bed or lake bed
c
Tiger, python, hawk
a
Marble
d
Orangutan
b
Limestone
2
Palm shoot, fig, jack fruit, coconut palm beetle
c
The limestone was heated. The rock melted
and then re-crystallised into marble.
3
a
Tiger, python
b
a
1. Weathering
2. Erosion
3. Sediments
4. Sedimentation
5. Heat
6. Pressure
Both eat spotted deer; python also eats
the fruit bat.
The rock cycle
Unit 4 Food chains and
food webs
Topic 4.1: Food chains, food webs
and energy transfers
Getting started
13
1
a
b
1
Activity: Draw food chains
a
A producer is a living thing (usually a
green plant) that can make its own food.
b
Fern, bean plant, palm tree
4 a Any three from:
fig → orangutan → python
fig → orangutan → tiger
fig → fruit bat → hawk
fig → fruit bat → python
jack fruit → fruit bat → hawk
jack fruit → fruit bat → python
palm shoot → fruit bat → hawk
palm shoot → fruit bat → python
palm shoot → spotted deer → tiger
palm shoot → spotted deer → python
jack fruit → orangutan → python
jack fruit → orangutan → tiger
palm shoot → orangutan → python
palm shoot → orangutan → tiger
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Living things
14 rice plants
9 caterpillars
5 frogs
2 kingfishers
a
The amount of energy gets less and less as
it is transferred through a food chain.
b
This is because not all of the energy in a
food a consumer eats is passed on to the
next link in the chain – some of the energy
is used up by the consumer and as heat.
Topic 4.2: Harm to food chains
and food webs
b
5
30
20
10
0
The kingfishers. This is because as you
move up the food chain, the same number
of pesticide particles are transferred to
fewer living things on each level.
The higher up the food chain, the more
pesticide particles are collected/enter the body
of the consumer.
a
Rice plants
b
Caterpillars
c
Frogs
d
Kingfishers
1
The farmer sprays pesticide onto the
producer/corn.
2
The pesticide moves through the food chain
in the bodies of animals that eat the sprayed
plants and the animals that eat them.
2
Eating the living thing
Corn + pesticide → snail → person
or
Corn + pesticide → snail → bird → person
3
Rice plant → caterpillar → frog → kingfisher
4
Learners should explain that the game shows
that toxic substances like pesticides move
through a food chain when a living thing eats
another living thing that has the pesticide in
its body. If animals eat a lot of living things
that contain the pesticide, they will accumulate
high levels of pesticides in their bodies.
3
14
40
Questions
1
Questions
50
Living things in the food chain
Getting started
Learners’ own ideas may include substances they
know of, such as oil, acids or pollution in general.
60
rs
5
Graph of pesticide particles accumulated
gfi
she
A consumer, such as a hawk, does not
depend directly on producers to get its energy
because it does not eat plants. A hawk eats
animals that get their energy from eating
plants, and in this way depends on energy
stored in the producers.
a
rs
4
4
illa
Energy is transferred from the producer when
a consumer eats the producer.
lan
3
ep
They use it to make food.
ric
2
Number of pesticide particles
From the Sun
ts
Questions
1
Average number of pesticide
‘particles’ collected
7
11
20
50
kin
A food web shows that living things eat a
range of other living things to obtain their
energy, not just one thing as shown in a food
chain (or similar answer).
This is a possible results table based on using
100 ‘particle’ tokens and a class size of
30 learners.
fro
gs
3
erp
5
Think like a scientist: Play a food
chain game
cat
b Any one from:
palm shoot → coconut palm beetle →
orangutan → python
palm shoot → coconut palm beetle →
orangutan → tiger
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Activity: Research information about
mercury in food chains
4
It re-uses plastics that would otherwise be
thrown away and end up in the oceans.
Learners’ presentations should include the
following information:
• Mercury gets into the environment when
mercury waste or chemicals containing mercury
are released by coal burning power plants,
factories or mines into the air, soil, rivers and
the sea.
• Mercury gets into food chains when it is
absorbed from the soil by plant roots, from the
air by plant leaves, or from the water by aquatic
plants and animals.
• Mercury moves through food chains when
living things eat other living things that have
absorbed mercury into their bodies.
• Mercury is harmful to living things because it
damages their bodies. For example, in humans
and other mammals, mercury damages the
nervous system. It can also affect growth and
reproduction in many animals.
5
The ecobricks are used to build day care
centres and pre-primary schools for children
in poor communities in South Africa.
6
a
Learners’ own ideas. For example, buy
fewer products that are packaged in
plastic; use paper drinking straws instead
of plastic straws; use re-useable shopping
bags or paper or cloth shopping bags.
b
Learners’ own answers. For example, to
prevent damage to food chains; to make
our environment look better.
Example of food chain:
shrimp
amount of mercury
small fish
green algae
Project guidance
Part 1
1 Animals in the food chains can mistake
plastics for food and swallow them. The
plastics get stuck in the animals’ digestive
systems and can kill them. Microplastics can
also stay in the bodies of the sea animals
and be passed through food chains. The
microplastics can have harmful effects inside
the body if they accumulate, especially in
consumers higher up the food chains.
15
1
a
Grasses, acacia tree
b
Termite, impala, zebra
c
Baboon
d
Three: lion, hyena, leopard
e Any three from:
grass → zebra → lion
grass → zebra → hyena
grass → zebra → leopard
grass → impala → lion
grass → impala → hyena
grass → impala → leopard
grass → baboon → lion
grass → baboon → leopard
grass → baboon → hyena
tuna fish
octopus
Check your progress
2
Microplastics form from larger plastics that
break down into tiny particles due to the
action of sunlight and waves.
3
Because there are lots of large plastics in the
oceans which keep on breaking down into
smaller and smaller pieces.
f Any two from:
acacia → termite → baboon → lion
acacia → termite → baboon → leopard
grass → termite → baboon → lion
grass → termite → baboon → leopard
grass → baboon → hyena → lion
grass → termite → baboon → hyena →
lion
or
acacia → termite → baboon → hyena →
lion
g
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
2
a
Dot plot of average number of particles taken in
3
4
green algae
shrimps
small fish
Living things in the food chain
b
4
c
3
d
120
e
Any two from pesticides, microplastics,
mercury, cadmium
Unit 5 Forces and
electricity
16
1
A satellite is an object that orbits a bigger
object in space.
2
An artificial satellite is put into space by
humans. A natural satellite is a satellite that
already exists in space.
3
Because of the force of gravity between the
Earth and the Moon.
4
His mass is the same but his weight is less on
the Moon than on Earth (learners will not
know this yet but it will be interesting to hear
what they think).
Yes
b
His weight will be less.
c
Gravity is less on the Moon than on Earth
because the Moon has a smaller mass
than the Earth.
Astronauts have to wear heavy suits and boots
to make it easier for them to adjust to walking
on the Moon’s surface. The smaller gravity on
the Moon makes walking more like floating if
the astronaut is not carrying extra weight.
When the astronaut tips the glass, the water
will go sideways. He will have to use a straw!
Think like a scientist: Measure the mass
and weight of objects
1
The forcemeter readings are ten times the
measuring scale readings.
2
Learners’ own responses. They should find
ALL measurements of weight are ten times
the mass.
3
One kilogram of mass has a weight of ten
newtons on Earth.
4
a
The mass of objects would be the same as
on Earth. Mass is the same everywhere.
b
The weight of objects would be different
to those measured on Earth. This is
because the Moon has a smaller force of
gravity than the Earth.
Topic 5.1: Mass and weight
Getting started
a
Activity 2: How gravity affects weight
in space
1
Zero gravity
2
Gravity
3
Bones become weak, muscles become weak,
confusion of up and down, for example.
4
They use and tie themselves to footholds
and handholds.
5
To try to keep their muscles working.
6
To help them remember which way is up.
Activity 1: What is the difference
between mass and weight?
7
Very little or nothing
8
The same as it was on Earth
1
She was not scientifically correct. She should
have said ‘The baby’s mass is 3.6 kg.’
9
They have to suck food out of sachets and
suck drinks up with straws.
2
An object’s mass remains the same wherever it
is. An object’s weight depends on the force
of gravity.
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Topic 5.2: The effects of forces
Getting Started
1
The ping-pong ball is at rest.
2
Yes, there are forces acting on it.
3
gravity
4
Activity 2: Identify the effects of forces
in ball games
1
2
3
normal force
4
4
The person is hitting the ball with a bat.
Think like a scientist: Investigate
and discuss the effects of forces on
an object
Learners observe and discuss the various points to
inform their answers to the questions.
Activity 1: The effects of forces
Make an object move: roll the ball along the table
towards the book.
5
a
He will catch the ball.
b
It will stop the ball from moving.
a
He will kick the ball.
b
The ball moves and changes direction.
a
She will hit the ball.
b
It will move and change direction.
a
Gravity and normal forces
b
The balls move, change direction when
they hit each other or the sides of the table
and stop when they drop into the pockets.
Learners’ own responses, such as throwing a
ball makes the ball change direction; catching
the ball stops the ball moving; bouncing a ball
against the wall makes a ball change direction.
Topic 5.3: Floating and sinking
Getting started
Possible answers:
1
It will float.
2
Learners are likely to say that it feels light
in weight.
3
It will sink.
4
Learners are likely to say that it feels heavy.
Change the shape of an object: press down on the
ball with your hand.
5
Learners might suggest the weight/mass is
spread across a large area which allows it
to float.
2
Think like a scientist 1: How does mass
affect floating and sinking?
Slow down a moving object: roll the ball along the
table with a cloth on it to create friction.
Stop a moving object: hold up a book on the table
to stop the ball.
Change the direction an object is moving in: flick
the ball sideways to someone else in the group.
gravity
Learners’ own responses
book
push
Activity: Fair testing, force diagrams
and writing a conclusion
1
normal force
3
gravity
push
friction
normal force
17
The ball moves, changes direction and
bounces off the table.
book
The control variables are the liquid in the large
container and the mass of the small plastic
container (these remain the same).
The independent variable is the total mass of
sand (or rice) you put in the small container
(this changes).
The dependent variable is the floating or
sinking of the container (this is what you
observe as a result of changing the total mass
of sand in the small container).
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
3
The type of liquid in the large container was
always the same; the same small container was
used each time; 10 g of sand was measured
with the same measuring scale each time.
a
6
18
16
Note that the gravity arrow should be the
same length as the upthrust arrow.
Graph showing the relationship between container’s
base area and the number of coins in it before sinking
14
Number of coins
2
gravity
12
10
8
6
4
2
0
upthrust
0
1
2
3
4
5
6
7
8
9 10
Area of base cm2
b
Note that the gravity arrow is longer than
the upthrust arrow.
gravity
The graph shows a positive trend.
Topic 5.4: Different circuits and
circuit diagrams
Getting started
upthrust
4
When the mass of the object is less than or
equal to the mass of water displaced by the
upthrust force, the object floats. When the
mass of the object is more than the mass of
water displaced by the upthrust force, the
object sinks.
Think like a scientist 2: How does
shape affect floating and sinking?
1 and 2 Learners should discover that a large,
flat-bottomed boat can carry a greater
number of marbles before sinking.
18
3
The larger the surface of the container in
contact with the water, the more likely the
object inside the container is to float.
4
An object of a certain mass that has a small,
compact shape will sink. An object of the same
mass with a larger, flatter shape will float.
5
a
Although the container ship has a large
mass, it has a large, flat shape that allows
it to float.
b
When the ship carries empty containers its
mass is less so it floats higher in the water
than when the containers are full.
1
Two cells, a switch, a lamp and connecting
wire.
2
No.
3
The switch is open so the circuit is broken and
the lamp will not light up.
Activity: Use circuit symbols to read
and draw circuit diagrams
1
a
Circuit B
b
Circuit A
c
Circuit C
2
Circuit B
3
Circuit B. It has a 3 V battery instead of a
1.5 V cell.
4
5
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Think like a scientist 1: Build circuits
with different components
In a series circuit there is only one path for the
electric current. If one lamp is removed from a
series circuit, the other lamp will not light up
because the circuit is broken.
In a parallel circuit, each lamp has its own
circuit. If one lamp is removed from a parallel
circuit, the other lamp will remain lit. The
remaining lamp will shine with the same
brightness as before.
1
A circuit with a cell,
A circuit with a
a lamp and a switch. battery, a switch and a
buzzer.
2
Learners should have concluded that the
buzzer would sound louder.
3
By adding another cell to the circuit.
4
a
Circuit B.
b
Circuit A only has a 1.5 V cell, which is
not strong enough for the buzzer to work;
circuit C has an open switch.
Think like a scientist 2: Make and
compare a series circuit and a parallel
circuit
1
Yes, the lamps shone more brightly in the
parallel circuit.
This is because, in a parallel circuit, the
full strength of the electricity goes to each
lamp. In a series circuit, the strength of the
electricity has to be shared between the lamps.
2
No: unscrewing one lamp broke the circuit.
3
Yes: the other lamp lit up. It shone with the
same brightness as before. This is because the
same strength of electricity goes to each lamp.
6
a
Circuit B is the series circuit and Circuit A
is the parallel circuit.
b
Circuit A. The lamps will shine more
brightly because each lamp has its own
circuit and receives the full strength of the
battery.
Check your progress
1
2
a
Grams (g) and kilograms (kg)
b
Newtons (N)
a
70 kg
b
700 N
c
70 kg
d
350 N
3
Force has:
• changed the shape of the car – it is crushed
• changed the position of the car – it has
overturned
• changed the movement of the car – it has
stopped
• changed the direction of movement of
the car – the car is on its roof facing the
opposite direction.
4
a and b
gravity
4
gravity
upthrust
upthrust
series circuit
5
19
parallel circuit
In a series circuit with two lamps and one
battery, the lamps will burn less brightly than
in a parallel circuit with two lamps and one
battery .
c
The duck has a mass equal to or less than
the mass of water displaced, so it floats.
The stone has a greater mass than the
mass of water displaced, so it sinks.
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CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Activity: How we see reflected light
1
A mirror, a lake with clear, still water
2
A mirror image
3
A is the incident ray; B is the reflected ray.
4
They could add another 3 V battery.
d
They could make a parallel circuit.
ra
y
c
y
ra
nt
de
It is a series circuit because the electric
current only has one path.
ci
in
b
normal
te
d
a
re
fle
c
5
Think like a scientist 1: Demonstrate
how light travels when it reflects
1
inc
ide
nt
ray
ed
ect
refl
Unit 6 Light and the
solar system
ray
Topic 6.1: Reflection
2
The angles were the same.
Getting Started
3
So that we could see that the light left the
mirror at the same angle as it arrived for any
angle.
4
When a ray of light reflects off a plane mirror
it makes the same angle with the normal as it
did when it arrived at the mirror (or similar).
1
The Sun
2
Light travels from the Sun to the tree.
Light reflects off the tree into Sofia’s eyes.
3
5
20
4
A smooth, shiny surface
5
Yes, all surfaces reflect some light otherwise
we would not see them.
Cambridge Primary Science – Baxter & Dilley © Cambridge University Press 2021
CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Think like a scientist 2: Make and test
a periscope
Think like a scientist 1: Demonstrate
how light travels when it refracts
1
1
2
3
A periscope is a device that uses mirrors to
allow you to see over the top of something in
front of you.
2
Learners could test their periscope in the
classroom to see things that are higher up,
while looking straight ahead. They could
position themselves below a window and hold
the periscope so that they could see through
the window.
incident ray
3
reflected ray
incident ray
reflected ray
4
Because the reflected ray from the top mirror
has to go straight down the periscope to the
bottom mirror.
5
Light travels from the Sun to the person on
the other side of the wall. Light reflects off
the person to the top mirror of the periscope.
Light reflects off the top mirror and travels
down the periscope to the bottom mirror.
Light reflects off the bottom mirror into your
eye.
6
By making the periscope taller.
7
Learners’ answers may include seeing the stage
at a concert or seeing a procession when there
are people standing in front of you, or for
seeing above water in a submarine.
Topic 6.2: Refraction
Getting started
Learners will think this is a trick! It is an optical
illusion . . . they will not know the complete
explanation because that is refraction – what the
topic is all about. But you could ask them if they
have any ideas why the arrows appeared to point in
the opposite direction – the fact that the light has
to travel through water and then air for example.
21
Learners’ own responses
4
The pencil wasn’t really bent.
5
The light passes through water, glass and air.
6
Light from the pencil travels through the water
in the glass and then bends when it passes
through the glass to the air.
7
The pencil appeared to be bent because the
light refracted when it moved from the water
through the glass to the air.
8
During the demonstration, the light travelled
from the card through the air, then through
the glass into the water, and finally out of
the glass and into the air once more before it
reached our eyes.
This means that the light bends once when it
travelled through the glass into the water, and
then it bends again when it travelled out of
the water through the glass and into the air.
As a result, the light rays cross and the arrows
appear to be turned around.
Think like a scientist 2: Make and test
a convex lens
1
It has the same bulging shape.
2
Light rays pass from the print through the
water drop and bend inward and converge at
a point just beyond the water drop. This point
where the rays converge is the focus and we see
the enlarged print.
3
Learners can discover their own answers.
Cambridge Primary Science – Baxter & Dilley © Cambridge University Press 2021
CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
Topic 6.3: The solar system
6
Learners should identify a pattern of waning
from full Moon to new Moon and waxing
from new Moon to full Moon.
7
Observing over time and pattern seeking.
Getting Started
1
The Sun, planets, moons, (and asteroids and
comets)
2
The Sun
3
A star emits/sends out light and a planet
reflects light.
4
The Moon travels around the Earth
Think like a scientist 1: Make a scale
model of the solar system
Activity 2: Identify phases of the Moon
1
Waning
2
1: full Moon; 2: last quarter;
3: waning crescent
3
New Moon
4
1
The Sun is represented by a tennis or cricket
ball and the planets by sugar grains, peas
and lentils.
2
The sizes of the planets and the distances from
the Sun are more to scale.
3
About 750 metres
5
29.5 days
Activity 1: The planets
6
The Moon’s orbit around the Earth.
waxing gibbous
1
Jupiter
2
Mercury
Check your progress
3
Mercury
4
Neptune
1
5
Venus
6
Jupiter
7
Neptune
8
Mercury
9
Mercury
10 Neptune
11 Saturn
12 Jupiter
13 Earth
14 Jupiter and Saturn
a
The bending of light is reflection/
refraction.
b
A piece of glass with a curved surface
is a lens/mirror
c
A periscope uses mirrors set at 90°/45°
angles.
d
When the lit up part of the Moon
becomes bigger over a period of days, the
Moon is waxing/waning.
e
The bent pencil in the glass of water is a
trick of the light/an optical illusion.
a
1 is an incident ray and 2 is a reflected ray
b
Equal
15 Uranus and Neptune
Think like a scientist 2: Observe and
describe the phases of the Moon
1–4
Do not expect learners to produce drawings
of the phases of the Moon for every day
of the month (this would be unnecessary
and not possible if it is overcast). A typical
week could be: :
Sun
Mon
cloudy
no
moon
Tue
Wed
cloudy
Thu
Fri
Sat
cloudy
cloudy
If a learner produces 30 perfect pictures of
the Moon when you know on many days it
was not possible to see the Moon, you will
know that they have made it up!
5
22
Learners should label phases on their drawings
– e.g. above they could label waxing crescent
2
3
A light ray from the stone travels through
the water and then bends or refracts when it
passes from water to air. The ray continues
to Sofia’s eye. However, Sofia’s normal line
of sight is a straight line to the stone, which
appears to be floating in the water higher up.
4
a
1: Earth; 2: the Moon; 3: Saturn;
4: Mercury; 5: the Sun; 6: Venus
b
365¼ days
c
29½ days
d
Body 3
Cambridge Primary Science – Baxter & Dilley © Cambridge University Press 2021
CAMBRIDGE PRIMARY SCIENCE 6: TEACHER’S RESOURCE
5
a
The Sun’s rays
b
Waxing
c
2=
first quarter
4=
full
7=
waning crescent
23
Cambridge Primary Science – Baxter & Dilley © Cambridge University Press 2021