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Primary 3 Science Semestral Assessment 2 (End of Year) Paper 4

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Questions

Primary 3 Science SA2 Examination 2026 (Version 4)

TuitionGoWhere Assessment Paper

Duration: 75 minutes
Total Marks: 100
Name: _________________________ Class: _______ Date: _______


Section A: Multiple Choice Questions (25 marks)

Choose the correct answer and write the letter (A, B, C, or D) in the brackets provided. Each question is worth 1 mark.


1. A fire is not a living thing even though it grows and needs air. This is because fire:

(A) Is not made of cells and cannot reproduce
(B) Is too hot
(C) Is orange in colour
(D) Moves around

( )


2. Which of the following is an example of something that was once living but is now non-living?

(A) Plastic bottle
(B) Cotton shirt
(C) Metal spoon
(D) Glass cup

( )


3. All living things respond to changes in their environment. Which example shows this?

(A) A stone rolling down a hill
(B) A plant growing towards the light
(C) A car moving on the road
(D) Water flowing in a river

( )


4. Which of the following materials would be BEST for making a handle for a hot pot?

(A) Copper
(B) Iron
(C) Wood
(D) Steel

( )


5. A toy designer needs a material that is waterproof, flexible, and colourful for making bath toys. Which material is BEST?

(A) Paper
(B) Wood
(C) Rubber
(D) Metal

( )


6. In a beetle's life cycle, the larva is called a grub. Which statement about the grub is TRUE?

(A) It looks exactly like the adult beetle
(B) It can fly and find food
(C) It eats a lot to prepare for the pupa stage
(D) It does not need to eat

( )


7. Which statement correctly compares a grasshopper and a butterfly?

(A) Both go through complete metamorphosis
(B) Both go through incomplete metamorphosis
(C) Grasshopper has 3 stages, butterfly has 4 stages
(D) Grasshopper has 4 stages, butterfly has 3 stages

( )


8. A frog's life cycle starts with eggs laid in water. Which statement about frog development is TRUE?

(A) Tadpoles have legs when they hatch
(B) Tadpoles breathe with lungs
(C) Tadpoles develop legs before losing their tail
(D) Adult frogs can only live in water

( )


9. Seeds can be dispersed by wind, water, animals, or explosion. Which feature helps seeds disperse by wind?

(A) Hooks and spines
(B) Light and fluffy structures
(C) Bright coloured fruits
(D) Hard outer shells

( )


10. During photosynthesis, which of the following is NOT needed by plants?

(A) Sunlight
(B) Carbon dioxide
(C) Water
(D) Oxygen

( )


11. Which statement about the function of flowers is CORRECT?

(A) Flowers absorb water from the soil
(B) Flowers make food for the plant
(C) Flowers help plants reproduce
(D) Flowers transport water through the plant

( )


12. A plant is watered but kept in complete darkness. After two weeks, what would you observe?

(A) The plant grows taller and greener
(B) The plant turns yellow and weak
(C) The plant produces many flowers
(D) The plant's roots grow longer

( )


13. Which sense organ would you use to tell if milk has turned sour without tasting it?

(A) Eyes
(B) Ears
(C) Nose
(D) Skin

( )


14. Which pair of sense organ and stimulus is CORRECTLY matched?

(A) Tongue - light
(B) Skin - sound
(C) Nose - smell
(D) Eyes - taste

( )


15. Danny stays up late playing video games and wakes up feeling tired. Which body system is most affected by lack of sleep?

(A) Digestive system
(B) Nervous system
(C) Muscular system
(D) Skeletal system

( )


16. Which is NOT a function of the skeletal system?

(A) Protecting vital organs
(B) Giving the body shape
(C) Pumping blood around the body
(D) Working with muscles for movement

( )


17. The food pyramid suggests we should eat more:

(A) Sweets and sugary drinks
(B) Meat and fish
(C) Fruits and vegetables
(D) Fried food

( )


18. Which of the following objects contains only NON-MAGNETIC materials?

(A) Steel ruler and iron nail
(B) Plastic cup and wooden block
(C) Nickel coin and steel spoon
(D) Iron gate and steel fence

( )


19. A student tested different objects with a magnet. Which result is INCORRECT?

(A) Paper clip - attracted
(B) Aluminium foil - not attracted
(C) Copper wire - attracted
(D) Steel scissors - attracted

( )


20. Why does a compass needle point north?

(A) The needle is painted to point north
(B) The needle is attracted to the geographic North Pole which is a magnetic south pole
(C) Wind pushes the needle north
(D) The compass has a motor inside

( )


21. A magnet can pick up paper clips through a thin piece of cardboard. This shows that:

(A) Cardboard is magnetic
(B) Magnetic force can act through non-magnetic materials
(C) Paper clips are not really magnetic
(D) The cardboard makes the magnet stronger

( )


22. Which statement about magnets is FALSE?

(A) Every magnet has a North and South pole
(B) Like poles attract each other
(C) Magnetic force is strongest at the poles
(D) Magnets can attract objects made of iron

( )


23. Magnets are used in all of the following EXCEPT:

(A) MRT card readers
(B) Refrigerator doors
(C) Compass needles
(D) Wooden furniture

( )


24. If a bar magnet is cut into three pieces, how many poles will there be in total?

(A) 2
(B) 3
(C) 4
(D) 6

( )


25. John has two bar magnets. When he brings them close, they push apart. This means:

(A) One magnet is broken
(B) Like poles are facing each other
(C) Unlike poles are facing each other
(D) The magnets have lost their magnetism

( )


Section B: Short Answer Questions (45 marks)

Answer all questions in the spaces provided.


26. (4 marks) Study the information about different organisms:

OrganismBreathesGrowsMovesReproduces
CoralYesYesNoYes
FireNoYesYesNo
MushroomYesYesNoYes
RobotNoNoYesNo

(a) Which organisms in the table are living things? Explain how you know. (2m)



(b) Fire seems to have some characteristics of living things. Why is it still classified as non-living? (2m)




27. (4 marks) Look at the materials and items table:

ItemMaterialWhy this material is used
WindowGlass?
TyreRubber?
PotMetal?
RaincoatPlastic?

(a) Complete the table by explaining why each material is used. (2m)



(b) A kitchen cutting board can be made of wood or plastic. Give ONE advantage of each material. (2m)

Wood: ____________________________________________________________

Plastic: __________________________________________________________


28. (5 marks) The diagram shows a mealworm's life cycle:

     Egg
      ↓
    Larva (mealworm)
      ↓
    Pupa
      ↓
    Adult (beetle)

(a) What type of metamorphosis does this show? (1m)


(b) Compare this life cycle with a cockroach's life cycle. State TWO differences. (2m)



(c) Why is the larva (mealworm) stage important for the beetle? (2m)




29. (4 marks) A gardener noticed the following about his plants:

Plant LocationObservation
Near windowTall, green leaves, leaning towards window
In dark cornerShort, yellow leaves, weak stems

(a) Why are the plants near the window growing towards it? (2m)



(b) What could the gardener do to help the plants in the dark corner? (2m)




30. (5 marks) Study the diagram showing gas exchange in a leaf:

                Sunlight
                   ↓
         [Carbon dioxide] → enters leaf
                           
        LEAF makes FOOD (glucose)
                           
         [Oxygen] ← leaves leaf
         [Water vapour] ← leaves leaf

(a) Name TWO things that enter the leaf for photosynthesis. (1m)


(b) What happens to the food (glucose) that the plant makes? (2m)



(c) Why do plants release oxygen, and why is this important for other living things? (2m)




31. (4 marks) Students recorded their classmates' daily habits:

StudentSleep hoursBreakfastScreen timeExercise
Amy10 hoursEvery day1 hourDaily
Benny6 hoursSometimes5 hoursNever
Carol8 hoursEvery day2 hours3x week

(a) Rank the students from healthiest to least healthy lifestyle. Explain your ranking. (2m)



(b) What changes should Benny make to improve his health? List TWO. (2m)




32. (5 marks) Complete the table about the five senses:

SenseSense OrganWhat it detectsExample
SightEyes
HearingSound/vibrations
SmellSmelling flowers
TasteTongue
TouchFeeling if water is hot

33. (4 marks) The skeletal and muscular systems work together for movement.

(a) Name TWO functions of the skeletal system besides movement. (2m)



(b) Explain how bones and muscles work together to bend your arm. (2m)




34. (5 marks) Study the magnet experiment results:

Experiment: Testing what magnets can attract through different materials

MaterialCan magnet attract paper clips through it?
PaperYes
GlassYes
WaterYes
Thin woodYes
Steel plateNo

(a) What pattern do you notice in the results? (2m)



(b) Why can the magnet not attract paper clips through the steel plate? (2m)



(c) How could you use this information to protect something from magnetic effects? (1m)



35. (5 marks) Study the diagram of magnetic poles:

Magnet A:  [S ═══════ N]
                     ↕
Magnet B:  [N ═══════ S]

(a) What will happen when these two magnets are brought close as shown? Explain why. (2m)



(b) How would you change the position of Magnet B so that the magnets repel? (1m)


(c) List TWO everyday uses of magnets and explain how they work. (2m)




Section C: Word Problems (30 marks)

Answer all questions with detailed explanations.


36. (8 marks) Classification Challenge

Scientists found some unusual organisms on an island. Here is what they observed:

OrganismMakes own foodMoves aroundGrowsResponds to touchHas cells
Specimen AYesNoYesYesYes
Specimen BNoYesYesYesYes
Specimen CNoNoYesNoNo
Specimen DNoYesNoNoNo

(a) Which specimens are definitely living things? Explain using THREE pieces of evidence for each. (4m)





(b) Specimen C grows but has no cells and doesn't respond to touch. What might it be? (Give an example of a non-living thing that grows) (2m)



(c) Why is "having cells" an important characteristic for identifying living things? (2m)




37. (8 marks) Life Cycle Investigation

A class observed three containers over 4 weeks:

Container 1: Caterpillars on leaves

  • Week 1: Caterpillars eating leaves
  • Week 2: Caterpillars formed chrysalis
  • Week 3: Chrysalis stage continues
  • Week 4: Butterflies emerged

Container 2: Grasshopper eggs

  • Week 1: Tiny nymphs hatched
  • Week 2: Nymphs growing bigger
  • Week 3: Nymphs developing wing buds
  • Week 4: Adult grasshoppers with full wings

Container 3: Mosquito eggs in water

  • Week 1: Wrigglers swimming
  • Week 2: Tumblers floating
  • Week 3: Adults emerged from water
  • Week 4: Adult mosquitoes flying

(a) Create a comparison table showing the differences between the three life cycles: (4m)

FeatureButterflyGrasshopperMosquito
Type of metamorphosis
Number of stages
Larva/young stage name
Does young look like adult?

(b) Why did the students keep the mosquito eggs in water? (2m)



(c) Which animal's young needs the most different habitat from the adult? Explain. (2m)




38. (7 marks) Garden Experiment

Three groups of students planted bean seeds in different conditions:

GroupSoil typeLightWaterFertilizerResult
AGood soilFull sunDailyYes40 cm tall, many leaves, dark green
BGood soilFull sunDailyNo30 cm tall, some leaves, light green
CSandFull sunDailyYes15 cm tall, few leaves, yellow

(a) Compare Groups A and B. What does this tell us about fertilizer? (2m)



(b) Group C had fertilizer but grew poorly. What do you think went wrong? (2m)



(c) Design an experiment to test if plants need light. Describe what you would do and what you would observe. (3m)





39. (7 marks) Magnet Problem Solving

A toy company wants to make a magnetic fishing game. They tested different materials:

Material testedAttracted to magnet?Can be used for fish?
Iron sheetYesYes
Plastic with iron coreYesYes
Pure plasticNoNo
AluminiumNoNo
CopperNoNo
Steel wireYesYes

(a) The company decided to make fish from "plastic with iron core." Why is this a better choice than pure iron? Give TWO reasons. (2m)



(b) A child complained that the magnet picks up fish even through the cardboard playing surface but won't work through the metal box lid. Explain why. (2m)



(c) The company wants to make the game harder by making some fish more difficult to catch. Suggest TWO ways they could do this using your knowledge of magnets. (2m)



(d) Why would copper or aluminium fish make the game impossible to play? (1m)



END OF PAPER


This paper covers all P3 Science topics: Diversity, Life Cycles, Plant Systems, Human Systems, and Magnets.

Answers

Primary 3 Science SA2 Examination 2026 (Version 4) - Answer Key

TuitionGoWhere Assessment Paper

Duration: 75 minutes
Total Marks: 100


Section A: Multiple Choice Questions (25 marks)

1 mark each

QAnswerExplanation
1(A)Fire is not living because it is not made of cells and cannot reproduce. It also doesn't need food.
2(B)Cotton shirt is made from cotton plants (once living). Plastic, metal, and glass were never living.
3(B)A plant growing towards light shows response to environment - a characteristic of living things.
4(C)Wood is a poor conductor of heat, so it won't become hot when touching the pot. Copper, iron, and steel conduct heat.
5(C)Rubber is waterproof, flexible, and can be coloured - ideal for bath toys.
6(C)The grub (larva) eats a lot to store energy for the pupa stage when it cannot eat.
7(C)Grasshopper has 3 stages (incomplete metamorphosis); butterfly has 4 stages (complete metamorphosis).
8(C)Tadpoles develop legs first, then gradually lose their tail as they become frogs.
9(B)Light and fluffy structures (like dandelion seeds) help seeds be carried by wind.
10(D)Oxygen is released during photosynthesis, not needed. Plants need sunlight, CO2, and water.
11(C)Flowers help plants reproduce by producing seeds (after pollination).
12(B)Without light, plants cannot make chlorophyll or food, so they turn yellow and weak.
13(C)The nose detects smell - sour milk has a distinct bad smell.
14(C)Nose detects smell. Eyes detect light, tongue detects taste, ears detect sound.
15(B)The nervous system (brain) is most affected by lack of sleep, causing tiredness and difficulty concentrating.
16(C)Pumping blood is the heart's function (circulatory system), not the skeletal system.
17(C)The food pyramid recommends eating more fruits and vegetables for good health.
18(B)Plastic and wood are both non-magnetic. All other options contain magnetic materials.
19(C)Copper wire is NOT magnetic and would NOT be attracted - this result is incorrect.
20(B)Earth's geographic North is a magnetic south pole, which attracts the magnet's north pole.
21(B)Magnetic force can pass through non-magnetic materials like cardboard.
22(B)FALSE: Like poles REPEL (not attract) each other.
23(D)Wooden furniture does not use magnets. The others all use magnets.
24(D)Each piece becomes a complete magnet with 2 poles. 3 pieces × 2 poles = 6 poles total.
25(B)Magnets push apart when like poles (N-N or S-S) face each other.

Section B: Short Answer Questions (45 marks)

26. (4 marks)

(a) Living things: Coral and Mushroom (2m)

  • They have all the characteristics of living things: breathe, grow, and reproduce (1m each)
  • Both are made of cells and carry out life processes

(b) Fire is classified as non-living because: (2m)

  • It is not made of cells (1m)
  • It cannot reproduce on its own (1m)
  • It does not need food
  • It does not respond to its environment in a living way

27. (4 marks)

(a) Why each material is used: (2m)

  • Window - Glass: Transparent, allows light through
  • Tyre - Rubber: Flexible, has good grip, durable
  • Pot - Metal: Conducts heat well for cooking, strong
  • Raincoat - Plastic: Waterproof, keeps rain out

(b) Cutting board material advantages: (2m)

  • Wood: Natural, gentle on knives, can be sanded if scratched
  • Plastic: Easy to clean, waterproof, can be sterilized, lightweight

28. (5 marks)

(a) Type of metamorphosis: Complete metamorphosis (1m)

(b) Two differences between mealworm and cockroach life cycles: (2m)

  • Mealworm has 4 stages; cockroach has 3 stages (1m)
  • Mealworm has a pupa stage; cockroach does not have a pupa stage (1m)
  • Mealworm larva looks different from adult; cockroach nymph looks like a small adult

(c) Why the larva stage is important: (2m)

  • The larva eats and grows, storing energy for the pupa stage (1m)
  • The larva stage is when most of the feeding and growing happens (1m)

29. (4 marks)

(a) Plants growing towards the window because: (2m)

  • Plants need sunlight to make food through photosynthesis (1m)
  • They grow towards the light source to get more sunlight (1m)

(b) To help plants in the dark corner: (2m)

  • Move them to a location with more light / near a window (1m)
  • Use artificial grow lights (1m)
  • Rotate plants regularly so all get sunlight

30. (5 marks)

(a) Two things that enter the leaf: (1m)

  • Carbon dioxide and water
  • (Or: Carbon dioxide and sunlight)

(b) What happens to the glucose: (2m)

  • The plant uses it for energy to grow (1m)
  • The plant stores it for later use / converts it to starch (1m)

(c) Why plants release oxygen and its importance: (2m)

  • Oxygen is a by-product of photosynthesis that the plant doesn't need (1m)
  • Animals and humans need oxygen to breathe and survive (1m)

31. (4 marks)

(a) Ranking from healthiest to least healthy: (2m)

  • Amy (healthiest) - gets enough sleep, eats breakfast, low screen time, exercises daily
  • Carol - good sleep and breakfast, moderate screen time, exercises regularly
  • Benny (least healthy) - not enough sleep, skips breakfast, too much screen time, no exercise (Award 1m for correct order, 1m for valid explanation)

(b) Changes Benny should make: (2m)

  • Sleep more (8-10 hours per night) (1m)
  • Exercise regularly (1m)
  • Eat breakfast every day
  • Reduce screen time

32. (5 marks - 1m for each correct row)

SenseSense OrganWhat it detectsExample
SightEyesLight / imagesSeeing a rainbow
HearingEarsSound/vibrationsHearing music
SmellNoseSmells / odoursSmelling flowers
TasteTongueFlavours / tastesTasting sweet food
TouchSkinPressure / temperature / textureFeeling if water is hot

33. (4 marks)

(a) Two other functions of the skeletal system: (2m)

  • Protecting vital organs (e.g., skull protects brain, ribs protect heart and lungs) (1m)
  • Giving the body shape and support (1m)
  • Making blood cells (in bone marrow)

(b) How bones and muscles work together to bend the arm: (2m)

  • Muscles are attached to bones by tendons (1m)
  • When the bicep muscle contracts (gets shorter), it pulls on the arm bones to bend the arm (1m)

34. (5 marks)

(a) Pattern in the results: (2m)

  • Magnets can attract through non-magnetic materials (paper, glass, water, wood) (1m)
  • Magnets cannot attract through magnetic materials (steel) (1m)

(b) Why magnet cannot attract through steel plate: (2m)

  • Steel is a magnetic material (1m)
  • The steel plate absorbs/blocks the magnetic force, preventing it from reaching the paper clips (1m)

(c) How to protect something from magnetic effects: (1m)

  • Surround it with steel or other magnetic materials to block magnetic force

35. (5 marks)

(a) What happens and why: (2m)

  • The magnets will attract each other (1m)
  • Because unlike poles (N of A faces S of B) attract each other (1m)

(b) To make magnets repel: (1m)

  • Flip Magnet B so that N faces N or S faces S (like poles facing each other)

(c) Two everyday uses of magnets: (2m)

  • Refrigerator door seal - magnets in the seal attract the metal door to keep it closed (1m)
  • Compass - the magnetic needle aligns with Earth's magnetic field to show direction (1m)
  • Magnetic pencil case / toys / speakers

Section C: Word Problems (30 marks)

36. (8 marks)

(a) Living things are Specimen A and Specimen B: (4m)

Specimen A (2m):

  • Has cells
  • Grows
  • Responds to touch
  • Makes own food (like a plant)

Specimen B (2m):

  • Has cells
  • Grows
  • Moves around
  • Responds to touch
  • Does not make own food (like an animal)

(b) Specimen C might be: (2m)

  • A crystal (like salt or sugar crystals) which can grow but is not living
  • Ice / Stalactite / other non-living things that can increase in size (1m for example, 1m for explanation that it's not made of cells)

(c) Why "having cells" is important: (2m)

  • All living things are made of cells - cells are the basic building blocks of life (1m)
  • Cells carry out all life processes like growth, reproduction, and metabolism (1m)

37. (8 marks)

(a) Comparison table: (4m)

FeatureButterflyGrasshopperMosquito
Type of metamorphosisCompleteIncompleteComplete
Number of stages434
Larva/young stage nameCaterpillarNymphWriggler/Larva
Does young look like adult?NoYesNo

(1m for each correct row)

(b) Why mosquito eggs were kept in water: (2m)

  • Mosquito eggs, larvae (wrigglers), and pupae (tumblers) all live in water (1m)
  • They need water to survive and develop (1m)

(c) Animal with most different habitat from adult: Mosquito (2m)

  • The young (wriggler) lives in water while the adult lives on land and flies in air (1m)
  • The butterfly and grasshopper young live in similar habitats to adults (on plants/land) (1m)

38. (7 marks)

(a) Effect of fertilizer (comparing A and B): (2m)

  • Group A (with fertilizer) grew taller (40 cm) than Group B (30 cm) (1m)
  • Fertilizer provides extra nutrients that help plants grow bigger and healthier (1m)

(b) Why Group C grew poorly: (2m)

  • Sand does not hold water or nutrients well (1m)
  • Even with fertilizer, the nutrients and water drained away too quickly for the plant to absorb (1m)
  • Plants need good soil that can hold water and nutrients

(c) Experiment design to test if plants need light: (3m)

  • Set up two identical plants with the same soil, water, and fertilizer (1m)
  • Put one in sunlight and one in complete darkness (1m)
  • After 2 weeks, observe and compare: the plant in light should grow well and stay green, while the plant in darkness should be weak, yellow, or dead (1m)

39. (7 marks)

(a) Why "plastic with iron core" is better than pure iron: (2m)

  • Plastic makes the fish colourful and attractive for children (1m)
  • Plastic is lighter and floats better in water; pure iron would be too heavy (1m)
  • Plastic doesn't rust like iron would

(b) Works through cardboard but not metal box lid: (2m)

  • Cardboard is non-magnetic, so magnetic force can pass through it (1m)
  • Metal (steel) is magnetic and blocks/absorbs the magnetic force (1m)

(c) Two ways to make the game harder: (2m)

  • Use a weaker magnet on the fishing rod (1m)
  • Place fish further from the surface / deeper (1m)
  • Make fish smaller (less magnetic material)
  • Add a non-magnetic barrier between magnet and fish

(d) Why copper or aluminium fish wouldn't work: (1m)

  • Copper and aluminium are not magnetic materials and would not be attracted to the magnet

Mark Summary

SectionMaximum Marks
Section A: MCQ25
Section B: Short Answer45
Section C: Word Problems30
Total100

Answer Key for TuitionGoWhere P3 Science SA2 2026 Version 4