Republic of Botswana

LOWER PRIMARY TEACHER’S GUIDE

FOR

ENVIRONMENTAL SCIENCE
SYLLABUS

STANDARD THREE

January 2004

Curriculum Development &Evaluation Department

Ministry of Education
Gaborone
Botswana
 CONTENTS

NOTES TO THE TEACHER ................................................................................................i

TOPIC 1.1: Care of the Surroundings....................................................................................1

TOPIC 2.1: Sky, Seasons and Weather .................................................................................4

TOPIC 2.2: Natural Resources ..............................................................................................9

TOPIC 3.1: Growing Plants ...................................................................................................15

TOPIC 3.2: Ourselves and Other Animals ............................................................................17

TOPIC 4.1: Personal Hygiene................................................................................................19

TOPIC 4.2: Safety..................................................................................................................23

TOPIC 4.3: Food and Nutrition .............................................................................................26

GLOSSARY ..........................................................................................................................31

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 NOTES TO THE TEACHER.

Please kindly note that the teacher’s guide is not a prescriptive document and should therefore
be used together with other resources materials for teaching Environmental Science. Teachers
are therefore encouraged to be as innovative as possible and conduct adequate research on the
various topics in order to plan and organise their learning environments. Collaborative teaching
and a learner-centred approach are strongly advocated for in this syllabus. However, how the
teacher achieves that is left for the teacher’s creativity and dexterity depending on the prevailing
conditions at the time and the available resources. The learning environment should be appealing
and exciting to learners.

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 TOPIC 1.1 CARE OF THE SURROUNDINGS

Introduction

Our surroundings need to be well cared for because any thing short of that would lead to an
environmental deterioration. Serious attempts have to be made not to create waste but if it is
generated, then it has to be properly disposed of.

Objectives

1.1.1.1 describe the terms re-use, reduce, and recycle

1.1.1.2 identify materials that can be reused, reduced and recycled
1.1.1.3 describe how waste can be reduced
1.1.1.4 demonstrate how materials can be re-used and reduced

Content

It is important to understand the internationally accepted waste management hierarchy: reduce,

re-use, recycle and safe landfill disposal. The pattern goes in this order:
i) reduce consumption or use
ii) if it cannot be avoided, re-use of materials should be the next option,
iii) if they cannot be re-used, then they have to be recycled and
iv) finally when all has failed, waste has to be safely disposed of at the landfill.

Basically when consumption is reduced, there will be less waste. If “reduce” is combined with
“re-use”, there is a further reduction in waste. A combination of reduce, reuse, and recycling,
drastically reduces waste to manageable levels to ensure a clean and healthy environment.

REDUCE

Reduced consumption leads to reduced

waste

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Reduce literally means minimising or stopping the use of a product. This practice leads to a
cleaner environment as generation of litter (waste) is minimised. E.g. stopping the use of plastic
bags for shopping will stop the problem of plastic waste, similarly, reducing the use of plastic
will reduce the amount that can be “waste”.

RE-USE

Use an item/material as many times as

possible

A grocery bag that is used over and over for subsequent buys is being re-used. A typical
example of re-use is of the use of our luggage bags. We do not throw them away after using them
once but keep using them until they are not usable anymore. As a result of this good practice
there is very little luggage bag waste. Soft drink glass bottles can be exchanged for some money
so that they can be cleaned and used again e.g. 1 litre Coke bottles.
The use of a product as a raw material for another is another way of reusing a material. For
instance using plastic from plastic bags as straps for the traditional arm chair

RECYCLE

Recycle to save energy, materials

and waste

The process of recycling involves the collection and processing of waste/rubbish to produce
other useful products. The products can be of the same kind or different.
Drink-cans may be recycled to produce new drink cans and other metal products, glass bottles to
produce new glass bottles and other glass items, aluminium to produce potato chips packets

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Learners should show appreciation of the waste management initiatives by practice. Some such
practices would be
1. to use toilet paper made from recycled paper to encourage recycling,
2. be frugal with toilet paper to reduce consumption
3. use grocery bags over and over again
4. stop wrapping items that already have wrapping to ‘reduce’
5. encourage the use of reusable nappies(diapers) not disposable ones to ‘reduce’ as
well as ‘reuse’

Suggested activities

1. engage class into an open discussion on the processes of reduce, re-use and recycle
2. collect different kinds of waste and classify it as reducible, reusable or recyclable
3. develop a class waste management ethics around the concepts “reduce, reuse, and
recycling

NB: Safety and health measures must be observed when collecting different kinds of waste.

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 TOPIC 2.1 SKY, SEASONS AND WEATHER

By now children have gained a lot of formal and informal experience and knowledge of the
environment. They are aware of seasons and can actually associate certain social and community
activities with certain times of the year e.g ploughing only during the rains and usually in the
months of November, December and January, weeding harvesting, winnowing etc all performed
at different times of the year. These activities in a way define seasons

Summer (Selemo) [ploughing season]: Dec-March. Weather is warmest.

Autumn (Letlhafula) [fresh farm produce in abundance;]: March-May i.e. when fruits
and crops become ripe and are gathered. Leaves fall.
Winter (Mariga) [time for harvesting]: May-Sept. Weather is coldest.
Spring (Dikgakologo) [preparing the fields for the next ploughing season]: Sept-Dec i.e.
weather becomes warmer. Leaves start to grow again and flowers
appear.

N.B The duration of a season is not steadfast, naturally a season may approach a little earlier
and extend beyond the expected period, or start late and extend beyond the expected
period or even start late and end early. Basically, the approach of a season is gradual
and so is its end.

Objectives

2.1.1.1 name the four seasons

2.1.1.2 describe each season
2.1.1.3 perform activities related to each season
2.1.1.4 relate weather conditions to the four season

Content

Generally human outdoor activities are dependent on the condition of the weather on any given
day. People may not go fishing on a rainy day but a sunny day, they may decide to wear warm
clothes because it is cold etc. Certain weather conditions are very common and predominant
during certain months of the year over extended periods of time, thus providing a conducive
environment for particular activities to be carried out.

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For instance, winnowing is done in winter when the grain is dry and also there is enough wind to
assist in the process.

Suggested activities

1. The seasonal activities help work out the characteristics of each season and possibly describe
the season. Questions such as the following might help in determining the characteristics of a
season.

[Q] During which months of the year are we likely to see more people on raincoats?
[A] The months of, December, January, February.

[Q] During which months is ploughing done?

[A] Dec-March.

[Q] What do you think people wear their raincoats for?

[A] To protect themselves against rain/avoid soaking.

[Q] Why is ploughing done during these months?

[A] Because the soil is moist.

Generalisations can then be drawn from these questions; such as

During the months of December, January, and February people plough (till the soil)
because the soil is wet (moist) and also wear raincoats because it is usually raining
therefore the period between Nov, and Feb is a wet period.

This season (summer) is therefore characterised by moisture:

1. list any activities that are done during the year
2. classify the activities as perennial, seasonal, monthly, daily etc
3. justify their choice of attire at different times of the year.
4. relate attire to seasons

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Objectives

2.1.2.1 recognise that wind is air in motion

2.1.2.2 demonstrate that wind has direction
2.1.2.3 find ways of determining wind direction
2.1.2.4 name the instrument used for determining the direction of wind
2.1.2.5 construct a simple wind vane
2.1.2.6 use a wind vane to determine the wind direction
2.1.2.7 record daily weather conditions
2.1.2.8 describe the effect of wind in the environment

Content

The space around us is filled with air. Most of the time this air is moving and when its movement
is felt, it is called wind. Wind always blows in some direction and the direction of the wind can
be determined using the wind vane or other methods e.g. sand, cloth on a stick (flag) method,
leaning of plants etc.

Suggested activities

1. engage the learners in an activity by which they will device means of determining the
direction of wind and also design instruments to determine the direction of wind.
2. take the learners to a weather station and allow them to use the wind vane to determine the
direction of wind. Take this exercise further by comparing the results of the wind vane to
those of their own instruments or methods
3. let the learners develop a chart and record the daily wind direction on it
4. learners can make diagrammatic representations of the effect of wind on the environment e.g.
diagrams of plants leaning, roofs being blown off the houses, paper flying, etc.

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Objectives

2.1.3.1 recognise that when light is obstructed shadows form

2.1.3.2 investigate how shadows change in size in relation to the position of the sun
2.1.3.3 use the size and cast of the shadow to estimate time

Content

The usefulness of shadows to man in keeping time dates to a long time back. Before the advent
of the modern day chronometer, the shadow was used as a timer because the shape and size of a
shadow changes with the position of the sun. Human beings harnessed this quality to keep time.

Suggested activities

1. take the learners to a place where there are trees or structures and study their shadows. Allow
the learners to choose a structure, mark the position of the shadow and record the time
corresponding to the position. Repeat this process for several shadow sizes/positions.
2. choose a convenient structure and mark shadow positions for significant times of the school
time table e.g. the start of school, start and end of morning break, lunch break, etc.

N.B The shadow positions change with seasons; the shadow position of a structure at 10:00
hours in winter is different from the shadow position of the same structure in summer at
the same hour. The changes in shadow positions are very pronounced especially between
winter and other seasons.

Objectives

2.1.3.4 observe that the moon is visible on some nights and sometimes in the day
2.1.3.5 observe that the shape and size of the moon changes

Content

The moon is a natural satellite orbiting the earth at a mean distance of 384400 km. It has a
diameter of 3474 km and takes 29 days to orbit the earth. While orbiting the earth, its position
relative to the earth and sun makes it change in size from new moon to full moon due to the
position of the shadow of the earth.

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Learners already know so much about the moon. They are already aware of the fact that the
moon changes in size.

Note: The moon orbits (revolves) around the earth while the earth orbits around the sun

Suggested activities

1. learners should be given an assignment stretching over a month to observe record and
draw the shape of the moon on a daily basis.
2. learners should use the collected data to determine the period between the new moon
and the full moon.

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 TOPIC 2.2 NATURAL RESOURCES

Introduction

Natural resources are resources (materials, substances etc) that occur in nature. They are not
man made and can only be harvested e.g. soil, water, plants etc. They are responsible for the
sustenance of life on earth. Water is needed by plants and animals to sustain life on earth. The
soil provides a home for animals and a medium on which plants grow. Plants are the primary
source of food and provide a home for other animals and raw materials for development.

Objectives

2.2.1.1 describe ways in which water can be polluted

2.2.1.2 describe ways of disposing of dirty water
2.2.1.4 list ways of preventing water pollution

Content

Water pollution can be caused by different activities. Human activities such as farming, industry,
etc can cause pollutants to dissolve in rivers, streams or even seep into the water table.
Pollutants from the pit-latrines and soak pits located very close to the water table may worsen
the problem of water pollution. Fertilisers used by farmers are washed from the soil into streams
(leaching). Some traditional practices such as washing linen (clothes) in streams, pools, ponds or
dams also contribute to the water pollution problem.

Suggested activities
1. Divide the class into groups of six(6) and let them do the following
a. brainstorm on the causes of water pollution
b. suggest ways of disposing of dirty water without causing pollution
c. suggest ways of preventing each one of the identified ways in which water can be
polluted
2. let the groups come together to share and discuss the different view points they bring from
their groups.
3. learners should find out about the position of the law on pollution and discuss that among
their groups.

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Objectives

2.2.1.3 make a soak pit

Content

Soak pits are mainly used in areas where the sewage system is not well developed. The soak pit
(soak away) enables the water in the drain to flow through and soak away into the soil. This
arrangement enables the drain to take longer before it is filled up. When the drain is full of
human waste, it can be emptied by pumping out the waste into a septic tanker to be disposed of
at a sewage treatment plant.

A DIAGRAM SHOWING A SOAK (SOAK AWAY) PIT

Membrane to prevent soil from

going into the perforations
between the rocks Soil

Inlet pipe

Pit
Rocks/stones

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The soak pit is made in such a way that the inlet pipe is at least 60 cm above the bottom of the
pit, that is, the minimum depth below the inlet pipe is 60 cm.
Although rocks of any size can be used, it is recommended that large rocks (stones) that create
large perforations (air spaces) between the rocks be used as water seeps easily through them
into the soil. Also the rocks that are placed at the mouth of the inlet pipe should be large enough
not to slide into the pipe and cause a blockage.
There is another way of constructing and using a soak pit. In this instance a hole is simply dug
and filled with rocks and stones but this time rocks and stones are not covered with soil. This
kind of soak pit is used mainly to hygienically controlling and disposing of dirty water.

A diagram showing a simple a soak pit

Pit filled
with Rocks/ston
rock/ston es
es

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Objectives

2.2.1.5 investigate common waterborne diseases in the community

2.2.1.6 describe symptoms of malaria and bilharzias (schistosomiasis)

Content

Though water is a very important natural resource, it had been known to assist in the
transmission of some diseases when contaminated. Diseases transmitted by direct contact with
water are known as water borne diseases e.g. cholera, polio, bilharzias etc. Such diseases are
transmitted through germs in water when someone drinks, swims, cooks, or walks through
contaminated water. In some cases, the water does not directly pass the disease, but helps in
maintaining the life cycle of the parasite or disease vector as in the case of malaria.

i) Bilharzias

The disease is caused by a flatworm (fluke) that lives in water. Human beings get it when they
swim, wash or walk through contaminated water. The small flukes barrow through the skin and
enter the bloodstream where they grow into adult flukes. Inside the human body the flukes stick
and hook themselves into the bladder or rectum walls, damaging some of the blood vessels,
causing some blood to mix with urine or faeces. The adult flukes then lay eggs that are passed
out with urine or faeces. If the infected person urinates or passes faeces near or in water the eggs
hatch into larvae and enter water snails where they develop into young flukes. The young flukes
then leave the snails and wait for the next victim in the water.

Signs and symptoms of bilharzias.

- the most common sign is blood in the urine, especially when passing the last drops
- pain may occur in the lower belly and between the legs, which becomes worse at the end of
urinating.
- low fever and itching may occur.
- after months or years the kidneys may be badly damaged causing general swelling or death.

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ii) Malaria

It is an infection of the blood that causes chills and fever. It is carried from one person to another
by mosquitoes. The mosquito sucks up the blood of the malaria parasites in the blood of an
infected person and injects them into the next person it bites. By so doing the parasite is passed
from an infected person to a healthy person who also becomes sick from malaria.

Signs and symptoms of malaria.

A typical malarial attack has three stages:

Stage 1: chills and often headache and weakness
continuous shivering for 15 minutes to 1 hour
Stage 2: fever (high temperature) that lasts several hours or days
the person is weak and at times confused (delirious)
Stage 3: Finally the person begins to sweat profusely and his temperature drops.

NB: Anyone suffering from inexplicable fevers should have their blood tested for malaria.

Suggested activities

1. discus with the learners a poster or diagram showing the life cycle of a bilharzias fluke
2. divide learners into groups of five and let them discuss in their groups (using the poster) how
the disease can be controlled and then report back to the class
3. discusss with the learners a poster or diagram showing the life cycle of a mosquito
4. divide learners into groups of five and let them discuss in their groups how malaria can be
controlled and then report back to the class

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Objectives

2.2.2.1 investigate the effect of running water and wind on soil

2.2.2.2 describe effects of running water and wind on soil
2.2.2.3 describe sources of soil erosion
2.2.2.4 state the effects of soil erosion on the environment
2.2.2.5 demonstrate the conservation of soil

Content

Soil erosion is the process through which the topsoil is lost. Running water and wind (agents of
soil erosion) carry the soil away. When the soil is carried away it carries with it some soil
nutrients making it difficult for plants to grow in the soil. Thus the land is left bare and barren
and further erosion results in small streams. These quickly transport rainwater before it can be
absorbed into the soil to replenish the water table. Soil can easily be destroyed by the methods
that we use in farming and cattle ranching.

Suggested activities

1. find a slope with some loose soil and pour water over it, observe and describe what happens
to the loose soil. There must be enough water to cause soil to erode.
2. visit vulnerable places in the village/town, assess and predict what will happen to them when
it rains. Keep a record of the situation and visit the place after the rains, compare the area
before and after the rains. Draw a conclusion about the effect of water on the soil using the
results.
3. do the same with covered soil and compare the results with those of the effect of running
water on bare soil
4. let learners explain what happens to the soil when the wind is blowing over it.
5. discuss the following under soil erosion
a. causes
b. effect
c. prevention (conservation of soil)

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 TOPIC 3.1 GROWING PLANTS

Introduction

Different seeds have different sizes and structures to enhance their ability to disperse and to
germinate. The ability of a seed to disperse and germinate depends on the nature and structure of
the seed.

Dispersal is a very important process for the survival of plants and their ability to grow. Some
seeds are small and feathery to be carried away by wind, others have hooks and spikes to stick to
the skins of animals, others have succulent and juicy fruits that are eaten by animals and others
can float on water so that they can be carried away from the parent plant by water. In this way
the plant is able to grow in new areas.

Some seeds have a hard coat to protect them from the adverse weather conditions like extreme
cold and fires. When suitable environmental conditions are available, the seed will germinate.
Seed germination requires water, warmth (suitable temperature) and air (oxygen). The time taken
by a seed to germinate is also dependent on the nature of the seed; a seed with a soft cover will
germinate faster than a seed with a very hard cover. While the seed is still germinating, it does
not require light because it obtains its food from the cotyledons until it has grown enough to
make its own food.

After germination there are certain conditions that should be met for the plant to grow normally
until it matures. The plant must get sufficient sunlight, water, air and soil nutrients.

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Objectives

3.1.1.1 observe characteristics of different seeds(size, colour, texture)

3.1.1.2 record difference between dry and soaked seeds
3.1.1.3 observe the period of time taken by different seeds to germinate
3.1.1.4 compare the effect of light and darkness on sprouting seeds seedlings
3.1.1.5 identify and name at least three vegetables
3.1.1.6 plant and observe a vegetable grow
3.1.1.5 measure vegetable growth in centimetres

Suggested activities

1. gather seeds and group them according to sizes, colour or texture etc

2. subject them to similar conditions and observe how long they each takes to germinate

3. divide the learners into groups of six and let them describe the seeds and come up with
reasons why they germinated at different times

4. let the learners place some seedlings in the dark and others in the light and compare the
growth results

5. plant a seed and measure its growth in centimetres (cm) and record any changes observed in
the plant.

6. get at least three types of vegetables and show them to the class. Let the class describe the
differences and similarities among the vegetables. Allow them to come up with other
examples of vegetables.

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 TOPIC 3.2 OURSELVES AND OTHER ANIMALS

Introduction

Every living creature on earth has an important part to play. For instance vultures rid the earth of
rotten carcasses while hyenas scavenge on remnants of other animals foods. All the animals do
these for their survival. This is the way of life in the animal kingdom. The availability of food
and the level of security in a place and the animals’ adaptations determine their habitats (i.e. an
area in which an organism or a community of organisms live). The animals and plants that share
a habitat are locked together in an interdependent community. For example, within a pond there
is a community of plants, micro-organisms and animals that form a food web. Habitats are
named after their major physical characteristics e.g. forest, river, grassland etc. within habitats
are small habitats known as microhabitats e.g. rotting log, mophane tree etc.
Naturally the environment has in place mechanisms (e.g disruption of a food chain or food web
by a decline in one or more species, alterations of conditions in the environment etc) that keep
the number of animals in a given area under check, thereby rendering the environment self-
sustaining. When the environment is self-sustaining, the ecosystem is referred to as balanced.
Droughts, indiscriminate human use of the natural resources or introduction of foreign species to
an ecosystem, usually promotes one species at the expense of another or others, thus causing
some imbalance to the ecosystem. The imbalance usually is destructive to the environment. This
is not the only process destructive to the environment. Animals can also contribute to this
problem e.g. elephants pulling down trees or cattle overgrazing a piece of land and others. Such
isolated activities have devastating effects on the lives of other species of animals that may not
necessarily be involved in the destruction as they may be destroying their habitats and food.

Suggested activities

1. let each learner name at least five domestic animals that they know and discuss their
usefulness to people :riding, milking, provision of meat etc.
2. repeat the steps in 1 but focussing on wild animals
(Make these activities very interactive, allow the learners to wonder in their discussions
so that the best is obtained out of them).

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3. Divide the class into groups of five and confine each group to a marked area, possibly
samples of different habitats/microhabitats

Instruction
a) estimate the size of the allocated area
b) list at least five wild animals in the area
c) choose three from the list and answer the following questions for each one of them
i. is it a vertebrate?
ii. what does it feed on?
iii. what are the common features of the area the animal lives ?
iv. name the animals habitat as grassland, river, water, woodland, etc?

Alternatively

4. name three animals and state what they eat, what their shelter is made of and also the
common features in its habitat

5. bring a rotting log into the classroom. It will contain a huge range of organisms and excite
considerable interest.

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 TOPIC 4.1 PERSONAL HYGIENE

Introduction

Personal hygiene can be described as the degree to which a person keeps himself or herself and
his or her surroundings clean to prevent diseases spread by germs. It involves taking proper care
of the body and living in clean surroundings. Germs can be spread by flies which like to breed in
refuse such as food scraps and peelings from fruits and vegetables. There must be a refuse pit
where household refuse is burned or buried everyday to ensure that the surroundings are clean.
The body can be taken care of by regularly bathing with soap, keeping the nails clean and short,
keeping the hair clean and combed, wearing clean clothes and regularly brushing teeth (oral
hygiene) with a fluoride tooth paste.

Objectives

4.1.1.1 demonstrate proper grooming.

Content

Cleanliness is very critical for ensuring a good personal hygiene. The body must be washed with
soap on regular basis, at least once daily. Nails must be cut short to prevent dirt and germs
accumulating between them. Clothes also need to be washed and ironed regularly. Washing
hands with soap and water removes germs from the hands. This prevents germs from getting into
food or into the mouth when handling food. It is particularly important to wash hands after
visiting the toilet and before handling food. This way many illnesses can be prevented.

Suggested activities

1. Learners should be inspected regularly to check if they adhere to the hygiene standards.
2. Have the learners wash their hands after visiting the toilet and before handling food.

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Objectives

4.1.1.2 investigate causes of tooth decay.

Content

Teeth are made of bone-like material and play an important role in cutting, grinding and mixing
food in the mouth. If the teeth are not taken proper care of, they may rot (tooth decay) and fall
off. Tooth decay is caused by germs in the mouth as a result of eating too much sugary foods,
particularly sweets, cakes, and sweet drinks. The sugar provides a breeding place for the germs.
The germs form an invisible layer called plague on the surface of the teeth. After a meal the
germs feed on any sugar present and turn it into acid. The acid is corrosive and eats into the
teeth causing holes and decay. If the germs eat deep into the teeth, the teeth begin to feel painful.
The germs may also get between the teeth and the gums, causing the gum to bleed.

Suggested Activities

1. Show the learners a picture of an adult teeth. Let the learners look inside their mouths with a
mirror and try to answer the following questions.
a) how many teeth have you got altogether?
b) which teeth, if any, do you lack and why?
c) what has happened to your teeth since you were five years?
d) which teeth if any have brown or grey cavities and why?

Objectives

4.1.1.3 describe ways of preventing tooth decay.

Content

To prevent tooth decay and a possible loss of teeth, proper care of the teeth should be
demonstrated right at an early age. There is need for teachers to emphasise this aspect of good
personal hygiene.

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Tooth decay can be prevented by;
- not eating or reducing sugary foods, particularly between meals to reduce the amount of acid
forming in the mouth.
- regular brushing of teeth using a toothbrush and fluoride toothpaste to remove the plague at
least twice a day, once in the morning and before going to bed.
- flossing the teeth to remove plague from between the teeth.
- rinsing and washing the mouth with water after every meal, particularly after eating
chocolates, sweets, etc and taking sweet drinks. Gums should be gently massaged at the same
time.
- visiting a dentist regularly (every six months or so) even if there is nothing wrong with the
teeth.

Suggested activities

1. learners should be allowed to bring their toothbrushes to school. They should then be allowed
to demonstrate the proper method of brushing teeth that removes food particles between
teeth. This entails brushing:
- the fronts of the teeth
- backs of the teeth
- between the teeth
- tops of the crowns
- the tongue

2. allow learners to develop posters to advice the public on how to prevent tooth decay.

NB: Under no circumstances should pupils be allowed to share their toothbrushes with anyone.

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Objectives

4.1.1.4 discuss the effects of substance abuse

Content

Substance abuse can have very devastating effects on the health of the person taking drugs.
Substance abuse, sometimes called drug abuse is the taking in of a drug or substance e.g.
alcohol, heroin, dagga, petrol, glue, cigarette smoking etc simply for enjoyment, often in large
amounts, which can lead to addiction. Addiction can lead the user into a life of crime to get
money or regular supplies of the drug.
Heroin is a substance normally taken by injection into the blood system. If several addicts use
the same unsterilised needles there are at a risk of contracting blood-borne diseases like
hepatitis and HIV and AIDS.
Alcohol is the most widely used drug and the most abused in many societies as it is generally
regarded as a socially acceptable drug. Addiction to alcohol is called alcoholism. Alcohol is a
depressant and slows reaction time and may lead to lack of self -control. It can also cause liver
damage that can eventually lead to death. It causes suffering to families due to financial
hardships and sometimes physical-violence.
Cigarettes contain a substance called nicotine, which is poisonous and increases heart rate and
blood pressure. It can also cause blood clotting that may block the blood vessels and cause a
heart stroke. Cigarette smoke also contains tar, carbonmonoxide and many other harmful
chemicals. The tar accumulates in the lungs and blocks the air spaces making breathing difficult.
Carbon-monoxide reduces the ability of blood to carry oxygen.

Suggested activities

1. Obtain a piece of liver and pour some dry gin on it while the learners are watching. Let the
learners discuss any changes they observed.
2. Design an experiment to demonstrate the effects of smoking on the lungs. Let the learners
discuss the observations.
3. Show a picture of a smoker’s lungs and healthy lungs to the class and allow the learners to
identify and state the differences.
4. Learners should be allowed to investigate from home the social and physical effects of
alcohol abuse and report back to the class.

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 TOPIC 4.2 SAFETY

Introduction

Safe practices (safety) have to be observed by all, at all times and in all the places and situations.
Such places/situation include roads, homes, playing fields, handling materials and chemicals etc.
Means of communication, as in alerting, warning, prohibiting as well as permission to interact
with certain situations or events are necessary. Different situations call for different and
sometimes specialised safety procedures. Such procedures range from the type of clothes worn to
the type of machinery used, storage of certain hazardous materials or chemicals, etc.
The high esteem by which safety is held is epitomised by the provision of services by certain
departments on issues of safety. These departments/safety service providers among others
include the army, the police, medics, lifeguards, coastguards, etc.

Objectives

4.2.1.1 observe road signs and marking

4.2.1.2 identify warning signs
4.2.1.5 name departments and personnel that ensure safety

Content

Nearly everybody uses the road daily, walking, driving, riding or cycling. In light of its extensive
use, it becomes imperative that rules, signs and regulations for its use are put in place. These
rules enable users to adopt a common road practice and understanding consequently minimising
the occurrence of accidents. Road signs and regulations have to be deliberately obeyed by all for
the safe use of the road. Signs can be of a regulatory nature wherein for instance the speed limit
is set, warning wherein a road user is alerted of the possibility of occurrence of certain thing
e.g. cross wind, animals crossing etc, informing in nature whereby the distance and direction to
a certain place is given. Note that these signs can be mounted on boards or marked on the road.
Failure to obey regulatory signs is punishable by law e.g. not wearing a seatbelt, over-speeding
etc. Failure to obey warning signs may cause fatal accidents e.g. moving at high speed on a sharp
curve or a slippery road. And failure to read information signs may result in one being lost.

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Suggested activities

1. safety of the kids is of paramount importance so that repeating or revising what they did at
standard 1 and 2 is doing no harm but helping the learners internalise road signs and proper
road use
a. let learners list all the road signs they can remember.
b. group them according to their functional categories: information, regulatory, warning.
c. discuss the role of police officers on the roads and paramedics in the event of an
accident.
d. invite a traffic officer or transport officer to your school/class to give a talk on road
safety.

Objectives

4.2.1.3 list at least four examples of protective clothing

4.2.1.4 explain the importance of protective clothing
4.2.1.6 identify hazardous household equipment, materials and substances
4.2.1.7 demonstrate proper handling of hazardous household equipment, materials and
substances
4.2.1.8 demonstrate proper storage of hazardous household equipment, materials and
substances.

Content

Life is surrounded by hazards. The roads we use are a hazard if not properly used, the chemicals
we use pose a danger to our well-being. Learners can only avoid these dangers if they are made
aware of their existence. Protection against these dangers can be achieved by wearing protective
clothing, formulating rules and regulations and also avoiding certain situations. Protective wear
such as helmets are worn in mining areas and construction cites for protection against falling
bodies, laboratory coats are worn in laboratories as protection for regular clothes and protection
against chemicals, plastic/rubber boots are worn in wet situations for protection against moist,
and many other protective clothes worn as per the dictates of the different situations

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Suggested activities

1. a. name the garden tools you have at home

b. describe at least three of the listed garden tools
c. discuss how each one of the above described tools could be dangerous
d. what can be done to prevent/avoid the perceived dangers

2. Divide the class into groups of 5 and make them answer the following questions
a. list any chemical you have seen at home e.g. pesticides, herbicides, kitchen detergents,
etc
b. describe at least three of the listed chemicals in terms of colour, viscosity ,use etc
c. outline the dangers that each chemical poses to your family
d. who are the most vulnerable group; children or adults?
e. why do you think the chosen group is the most vulnerable?
f. what can be done to eliminate /minimise the danger?
g. What can be done to ensure the safety of the vulnerable group/individual?

[Issues of storage, handling can be discussed here]

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 TOPIC 4.3 FOOD AND NUTRITION

Introduction

Every living thing depends on nutrition, the taking in of food and the use of that food for
survival. Plants make their own food. Animals obtain their food by either eating plants or eating
other animals that have eaten plants
Our choices of food and food habits have a very big impact on our health. The foods that can be
obtained from plants or animals provide us with nutrients. It should be noted though that the
dietary habits in different parts of the world differ according to the local availability of food. The
nutrients obtained have specialised functions in the body.

Energy giving foods: to enable the body to carry out all its functions (carbohydrates and
fats)

Body building foods: for growth and repair of body tissues (proteins)

Protective foods: those that prevent the advent of deficiency diseases and sustain
chemical reactions in the body (vitamins and minerals)

The three classes of food described above are some of the seven constituents of our diet. A
proper diet should constitute of carbohydrates, fats, proteins, minerals, vitamins, water and fibre.
For animals to be healthy, their diet must contain the food nutrients in their correct amounts. A
diet with the correct amount of each nutrient is called a balanced diet.

Water is acts as a solvent for chemical reactions in the body. It is the medium for all chemical
reaction and also helps to cool the body. Plant fibre keeps the food moving along the gut and
prevents constipation. It also reduces the amount of fat absorption in the gut.

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Objectives

4.3.1.1 classify foods according to their sources (plant and animal)

4.3.1.2 group foods according to their function in the body
4.3.2.1 find out the kinds of foods eaten at different times of the day
4.3.2.2 describe meals of the day
4.3.2.3 plan a meal
4.3.2.4 list foods that are suitable for different meals of the day
4.3.2.5 describe unhealthy eating habits
4.3.2.6 demonstrate healthy eating habits

Content

Food classes according to source

Food can be grouped according to whether it comes from plants or from animals. Carbohydrate
foods are manly from plant sources, while protein foods are mainly from animal sources.
Vitamins and minerals are mostly from plants, i.e. fruits and vegetables. Fats can be obtained
from plants and animals. Plants are also the only source of fibre.

Plant foods

Plant foods are those that come directly from plants or after processing plant products. Examples
include: beans, nuts, cereals, bread, potatoes, mealie meal, fresh fruits and vegetables,
pumpkins, morula, moretlwa, thepe, cabbage, oranges, pure fruit juices, honey, cornflakes, sugar
cane, watermelons, cooking oil, margarine etc.

Animal foods

Animal foods are those that come directly from animals or after processing animal products.
Examples include: beef, chicken, fish, pork, eggs, egg yolk, milk, yoghurt, cheese, Vienna’s and
polony, butter, cream etc.

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GROUPING FOODS ACCORDING TO FUNCTION

Foods can also be grouped according to what they do in the body.

Body building; beef, chicken, fish, egg yolk, peanuts, peas, milk etc.
Energy giving: bread, cereals, mealie meal, sorghum, millet, fats, honey, milk etc.
Protective: pumpkin, thepe, delele, rothwe, cabbage, fruits, fruit juices, milk etc.

MEALS FOR THE DAY

BREAKFAST

Protein: eggs, sausages, milk, beans, peas, groundnuts etc.

Carbohydrates: breakfast cereals, bread, beans,etc
Protective: oranges, peaches, fruit juices etc.

LUNCH

Protein: chicken, beef, fish, beans etc.

Carbohydrates: mealie meal, millet, potatoes, bread etc.
Protective: rothwe, cabbage, carrots, fruits, fruit juice etc.

SUPPER

Body building: beef, sausages, and fish

Carbohydrates: bread, fish, millet
Protective: carrots, cabbage

PLANNING A MEAL

A meal must be planned in such a way that it contains all the essential food nutrients. This
constitutes a balanced diet. A balanced diet is a varied diet that contains carbohydrates, proteins,
minerals and vitamins, water and roughage in the right propositions.

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MEAL SAMPLES

1 2 3 4
Seswaa serobe Beef Stew Seswaa
Samp Mealie meal Rice Mealie meal
Pumpkin Pumpkin Coleslaw Salad Thepe
Pumpkin

UNHEALTHY EATING HABITS.

A person’s diet may be unsuitable for healthy growth for two main reasons. The balance of
nutrients is incorrect leading to malnutrition. And when there is insufficient quantity of
nutrients leading to starvation. Malnutrition may cause such effects as constipation, heart
disease and obesity (overweight). Starvation results in very restricted growth and development,
particularly of muscles leading to weakness. Resistance to disease is severely reduced and death
eventually follows. Some unhealthy eating habits are listed below:

1. eating the wrong type of food

2. eating wrong combinations of food
3. under eating
4. over eating

Unhealthy eating habits or eating disorders may result in deficiency diseases or physical
disorders. Obesity results when a person eats more than what the body requires (over-eating).
The most fattening foods are those that provide the most energy, such as bread and margarine,
cake and sweets. It is unhealthy to eat “junk foods” as most of them are oily and fatty and the fat
then builds under the skin. Anorexia results when a person eats very little (under eating). It
stems from an obsessive fear of becoming fat. This is mostly common among teenage girls
because thereat a stage when they are very conscious of their physical appearances. The person
becomes thin and frail and if not treated, they may die.

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Suggested activities

1. name the common foods taken at different times of the day

2. Describe different meals of the day
- breakfast, lunch, supper or dinner
- the times the meals are taken
- foods that characterise breakfast ,lunch, supper and dinner
- how easily or difficult the food is prepared
- suggest why certain foods are preferred for certain meals
3. Share ideas on the following feeding habits
- fast foods
- junk foods
- over indulgence in certain foods without regards for its nutritive value
4. engage the whole class in an open discussion about what would constitute a good eating
habit.
5. let the learners discuss the effects of being over weight and being malnourished in their
groups and then make presentations to the class.

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 GLOSSARY

Adaptation: The ability of a plant or animal to survive in its environment.

The structure or functioning of an organism that makes it better suited to
its environment.
Anorexia: a condition of being excessively underweight caused by under eating.
Balanced diet: A meal that contains all the food nutrients in the right proportions.
Carcass: The remains of a dead animal.
Chronometer: An instrument used to measure time of the day.
Conservation: The sustainable use of a natural resource or product.
Constipation: A condition of hardening of digestive waste in the large intestine (colon)
due excess absorption of water.
Deficiency diseases: Diseases that are caused by lack of certain nutrients in a diet.
Diet: The kind of food and quantities humans and other animals usually eat and
drink.
Dietary habits: Feeding preferences.
Ecosystem: A biological community of plants and animals and the physical
environment associated with it.
Environment: The surroundings in which animals and plants live, including all the
conditions that affect the way of life of the organisms e.g. temperature,
humidity, light etc.
Food habits Feeding preferences see dietary habits
Habitat: The place where an organism lives (e.g. streams, ponds, rivers, woods etc)
which is characterised by its physical features (i.e. humidity, temperature,
light etc) or by the dominant plant types.
Harvesting: The act of gathering or collecting ripe crops e.g. grain, fruits etc.
Hazardous: Capable of causing harm i.e. dangerous.
Imbalance: A condition in which two or more things are not equally or fairly spread or
balanced.
Leaching: The washing away of soluble nutrients (mineral salts) from the soil.
Malnutrition: Bad health caused by the intake of unbalanced nutrients in ones diet.
Microhabitat: A small area within a habitat occupied by certain animals or plants.
Natural resource: Any naturally occurring organism or object that is essential for the
sustenance of life.
Obesity: The state of being overweight caused by unhealthy eating.
Orbit: To move around a body or object in a circular path.

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Organism: A living animal or plant.
Perennial: Describes plants that have a life cycle of more than two years.
Lasting a very long time, or happening repeatedly or all the time.
Pollutant: Any substance or material that affects the environment such that it
becomes unbearable for organisms living in it.
Pollution: A condition of damaging and poisoning the natural environment.
Reduce: To cut-down (i.e. use less) on the use or consumption of a material.
Recycle: To reprocess materials no longer needed for their original purpose to make
new products.
Re-use: To use the same material more than once in its original form e.g. plastic
bag.
Revolution: The movement around a circular or elliptical path. A complete circular
motion.
Rotation: The circular motion by a body or object around a fixed point.
Roughage: Dietary fibre obtained from plant food.
Satellite: A body or object that orbits a larger body in space.
Season: A part of the year associated with a type of weather and with natural
events that are affected by the weather.
Scavenge: To look for food from other people’s unwanted rubbish.
To feed on the flesh of dead decaying animals.
Scavenger: A bird or animal that feeds on waste material e.g. dead animals and the
remains left by other animals e.g. vultures and crows.
Seedling: A young plant grown from a germinating seed.
Seed dispersal: The transfer of seeds from the parent plant from one place to another by
wind, animals or water
Soak-pit: A pit dug beside a sewage drain to soak away the liquid waste.
Soil erosion: The washing away of soil from one place to another either by water or
wind.
The gradual wearing away of weathered rocks by the action of wind, rain,
rivers and sea.
Species: A group of animals or plants with identical distinguishing features and
characteristics.
A classification unit used to describe a group of similar individuals that
can usually breed among themselves and produce fertile offspring.

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Sprout: To produce leaves and other new developing parts in a plant or to begin to
grow.
A newly grown part of a plant.
Viscosity: A measure of how easily a liquid can flow OR the thickness of a liquid. A
liquid with a high viscosity (thick liquid) does not flow as easily as a
liquid that has a low viscosity (thin liquid)
Waste: Materials that are no longer needed in their original form and cannot be
used for any other purpose.
Waterborne: Carried by or through water.
Water Table: A spongy rock found underground that holds water that had soaked in the
ground after rains.
Weather: The state of atmospheric conditions, including humidity, precipitation (e.g.
rain, hail), temperature, cloud cover, visibility and wind at any one place
and time.
Weeding: To clear the ground of plants growing where they are not wanted (weeds)
in a garden or cultivated area
Wind vane: An instrument used to determine wind direction.
Winnowing: To blow the outer covering of grain (chaff) after thrashing (e.g. sorghum,
maize etc) using wind.

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