Natural Physical Science

Turning Effect of Force -Meaning of moment of force
Turning Effect of Force -Factors affecting turning effect
Turning Effect of Force -Calculating moment (M = F × d)

By the end of the lesson, the learner should be able to:
- Define the term moment of a force
- Identify the pivot and line of action of force in everyday tools
- Relate the concept of turning effect to real-life tools such as spanners, door handles and water pumps
- State the formula for moment of a force as M = F × d
- Calculate the moment of a force given force and perpendicular distance
- Relate moment calculations to real-life tools such as spanners and crowbars

In groups, learners are guided to:
- Use digital devices or print media to research on moments of a force at a point
- Discuss the meaning of a moment of a force and identify its components (force, pivot, perpendicular distance)
- Share findings with classmates and make short notes
- Work through examples of calculating moments using M = F × d
- Solve numerical problems involving moment of a force about a pivot
- Discuss and compare answers with peers

Why is it easier to open a door by pushing at the edge than near the hinge?
How do engineers use the moment formula when designing tools like wrenches and levers?

- Humming Bird General Science Learner's Book pg. 252
- Digital resources
- Reference books
- Spanners, lift pump, metre rule
- Humming Bird General Science Learner's Book pg. 254
- Calculator
- Reference books

- Oral questions - Observation
- Written assignments - Oral questions

Natural Physical Science

Turning Effect of Force -Principle of moments
Turning Effect of Force -Calculations using principle of moments

By the end of the lesson, the learner should be able to:
- State the principle of moments
- Demonstrate the principle of moments by balancing a metre rule
- Relate the principle of moments to balancing systems such as seesaws and beams

In groups, learners are guided to:
- Suspend a metre rule at its centre and hang known masses on either side
- Adjust positions until the rule balances horizontally
- Measure distances and calculate clockwise and anticlockwise moments
- Discuss findings and state the principle of moments

How does a seesaw balance when people of different weights sit at different distances from the centre?

- Humming Bird General Science Learner's Book pg. 256
- Metre rule, string, known masses, stand
- Digital resources
- Calculator
- Reference books

- Observation - Oral questions

Natural Physical Science

Turning Effect of Force -Moments due to beam weight

By the end of the lesson, the learner should be able to:
- Explain how the weight of a uniform beam contributes a moment about a pivot
- Calculate moments due to beam weight acting at its centre of gravity
- Relate beam weight moments to practical structures such as see-saws and bridges

In groups, learners are guided to:
- Discuss how a uniform beam's weight acts at its midpoint
- Solve problems involving a beam pivoted near one end with a spring balance maintaining equilibrium
- Calculate the weight of the beam from the spring balance reading and distances

Why does a uniform plank tip to one side when a person stands near its end even without additional weights?

- Humming Bird General Science Learner's Book pg. 258
- Metre rule, spring balance, stand
- Calculator

- Written assignments - Observation

Natural Physical Science

Turning Effect of Force -Antiparallel forces
Turning Effect of Force -Calculations on antiparallel forces

By the end of the lesson, the learner should be able to:
- Define antiparallel forces and describe how they act on an object
- Distinguish between a single force and a couple (antiparallel forces)
- Relate antiparallel forces to everyday examples such as turning a bicycle handlebar or steering wheel

In groups, learners are guided to:
- Watch animations or simulations on moments of antiparallel forces using a digital device
- Attach Newton balances at both ends of a wooden strip and compare force required to rotate the strip with one and two balances
- Discuss findings with peers

How does a driver use two hands on a steering wheel to turn it more effectively than using one hand?

- Humming Bird General Science Learner's Book pg. 260
- Wooden strip, Newton balances, screw
- Digital resources
- Humming Bird General Science Learner's Book pg. 261
- Calculator
- Reference books

- Observation - Oral questions

Natural Physical Science

Turning Effect of Force -Real-life applications and importance
Linear Motion -Distance and displacement

By the end of the lesson, the learner should be able to:
- Identify applications of turning effect of force in the kitchen, classroom, playground and parking lot
- Explain the importance of turning effect in tools and body movements
- Relate turning effect of force to daily activities such as pedalling a bicycle, using a crowbar and turning a doorknob
- Define distance and displacement and state their SI units
- Distinguish between distance and displacement using practical examples
- Relate the difference between distance and displacement to navigation and everyday travel

In groups, learners are guided to:
- Walk around the school to identify applications of turning effect of force
- Watch video clips on how turning effect of force is applied in real-life situations
- Discuss findings with classmates and write brief notes on applications and importance
- Mark points A, B and C in the field using pegs
- Measure the length AC through B (distance) and the straight line AC (displacement)
- Record and discuss the differences between the two measurements with peers

How does understanding the turning effect of force help engineers design more efficient tools and machines?
Why does a GPS device show a shorter distance to a destination than the actual road distance travelled?

- Humming Bird General Science Learner's Book pg. 263
- Digital resources
- Internet access
- Humming Bird General Science Learner's Book pg. 269
- Tape measure, pegs, hammer
- Reference books

- Oral questions - Observation

Natural Physical Science

Linear Motion -Calculations on distance and displacement

By the end of the lesson, the learner should be able to:
- Calculate distance and displacement from given data
- Solve problems distinguishing between total path length and straight-line change in position
- Relate distance and displacement calculations to real-life journeys such as athletes on a track

In groups, learners are guided to:
- Solve numerical problems involving distance and displacement
- Work through examples where a body moves in different directions and calculate both distance and displacement
- Compare solutions with peers

How would you calculate the displacement of a runner who completes two laps of a circular track?

- Humming Bird General Science Learner's Book pg. 270
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Calculations on distance and displacement

By the end of the lesson, the learner should be able to:
- Calculate distance and displacement from given data
- Solve problems distinguishing between total path length and straight-line change in position
- Relate distance and displacement calculations to real-life journeys such as athletes on a track

In groups, learners are guided to:
- Solve numerical problems involving distance and displacement
- Work through examples where a body moves in different directions and calculate both distance and displacement
- Compare solutions with peers

How would you calculate the displacement of a runner who completes two laps of a circular track?

- Humming Bird General Science Learner's Book pg. 270
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Speed and velocity

By the end of the lesson, the learner should be able to:
- Define speed and velocity and state their SI units
- Distinguish between speed and velocity
- Relate the difference between speed and velocity to real-life motion such as cars on a straight road and roundabouts

In groups, learners are guided to:
- Study pictures of cars in motion and discuss the difference between speed and velocity
- Discuss with peers why velocity requires direction while speed does not
- Write brief notes on the differences between speed and velocity

Why does a car moving at a constant speed around a roundabout have a changing velocity?

- Humming Bird General Science Learner's Book pg. 272
- Digital resources
- Reference books

- Oral questions - Observation

Natural Physical Science

Linear Motion -Practical determination of velocity
Linear Motion -Calculations on speed and velocity

By the end of the lesson, the learner should be able to:
- Determine velocity practically by measuring distance and time
- Record and analyse motion data to calculate average velocity
- Relate practical velocity measurements to real-life scenarios such as timing athletes and vehicles
- Calculate speed and velocity using appropriate formulae
- Solve numerical problems involving speed, distance and time
- Relate speed and velocity calculations to transport and athletics

- Mark a measured distance in the field and time a learner walking or running across it
- Calculate velocity using v = distance ÷ time
- Repeat with different distances and compare results
- Solve numerical problems on speed and velocity using v = s/t
- Work through examples involving vehicles, runners and cyclists
- Discuss and compare solutions with peers

How do traffic officers use speed guns to measure the velocity of vehicles on a highway?
How does a bus company use average speed calculations to plan arrival times between towns?

- Humming Bird General Science Learner's Book pg. 272
- Tape measure, stopwatch, pegs
- Calculator
- Humming Bird General Science Learner's Book pg. 272
- Calculator
- Reference books

- Observation - Written assignments
- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Calculations on speed and velocity

By the end of the lesson, the learner should be able to:
- Calculate speed and velocity using appropriate formulae
- Solve numerical problems involving speed, distance and time
- Relate speed and velocity calculations to transport and athletics

In groups, learners are guided to:
- Solve numerical problems on speed and velocity using v = s/t
- Work through examples involving vehicles, runners and cyclists
- Discuss and compare solutions with peers

How does a bus company use average speed calculations to plan arrival times between towns?

- Humming Bird General Science Learner's Book pg. 272
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Acceleration

By the end of the lesson, the learner should be able to:
- Define acceleration and deceleration and state their SI units
- Distinguish between acceleration and deceleration using practical examples
- Relate acceleration and deceleration to everyday situations such as vehicles speeding up or braking

In groups, learners are guided to:
- Discuss the meaning of acceleration as the rate of change of velocity
- Identify examples of acceleration and deceleration in daily life such as a bus pulling away from a stop and braking at a stage
- Write brief notes on acceleration and deceleration

How does a car manufacturer use acceleration values to describe the performance of a vehicle?

- Humming Bird General Science Learner's Book pg. 274
- Digital resources
- Reference books

- Oral questions - Observation

Natural Physical Science

Linear Motion -Calculations on acceleration and deceleration

By the end of the lesson, the learner should be able to:
- Calculate acceleration and deceleration using a = (v
-u) / t
- Solve numerical problems involving uniform acceleration and deceleration
- Relate deceleration calculations to road safety situations such as braking distances

In groups, learners are guided to:
- Solve problems involving vehicles accelerating from rest or decelerating to a stop
- Work through examples including converting km/h to m/s before solving
- Discuss how deceleration affects stopping distance on roads

How does a driver's reaction time affect the total stopping distance when braking on a highway?

- Humming Bird General Science Learner's Book pg. 274
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Equations of motion (v = u + at)

By the end of the lesson, the learner should be able to:
- State and apply the equation v = u + at
- Identify the variables of motion: initial velocity, final velocity, acceleration and time
- Relate the first equation of motion to real-life situations such as a car accelerating from rest

In groups, learners are guided to:
- Introduce the five variables of motion using a table (u, v, a, s, t)
- Solve problems using v = u + at where three variables are known
- Work through examples involving vehicles, boulders and runners

How would you use v = u + at to find the speed of a matatu after accelerating for a given time from rest?

- Humming Bird General Science Learner's Book pg. 276
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Equations of motion (s = ut + ½at² and v² = u² + 2as)

By the end of the lesson, the learner should be able to:
- State and apply the equations s = ut + ½at² and v² = u² + 2as
- Select the appropriate equation of motion based on the known and unknown variables
- Relate equations of motion to real-life problems such as calculating braking distance of vehicles

In groups, learners are guided to:
- Solve problems using s = ut + ½at² and v² = u² + 2as
- Work through mixed examples requiring selection of the correct equation
- Discuss and compare solutions with peers

How do road engineers use equations of motion to design safe stopping distances on highways?

- Humming Bird General Science Learner's Book pg. 276
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Free fall and gravity

By the end of the lesson, the learner should be able to:
- Define free fall and explain the effect of gravity on falling bodies
- Describe how air resistance affects falling objects of different shapes
- Relate free fall to real-life situations such as falling objects on construction sites and skydiving

In groups, learners are guided to:
- Drop a stone and a flat paper simultaneously and observe which hits the ground first
- Repeat the experiment with the paper folded into a tight ball and compare results
- Discuss how air resistance affects the paper but not the stone and relate to vacuum conditions

Why do skydivers open parachutes to slow their fall rather than falling freely to the ground?

- Humming Bird General Science Learner's Book pg. 283
- Stone, paper, writing materials
- Digital resources

- Observation - Oral questions

Natural Physical Science

Linear Motion -Free fall and gravity

By the end of the lesson, the learner should be able to:
- Define free fall and explain the effect of gravity on falling bodies
- Describe how air resistance affects falling objects of different shapes
- Relate free fall to real-life situations such as falling objects on construction sites and skydiving

In groups, learners are guided to:
- Drop a stone and a flat paper simultaneously and observe which hits the ground first
- Repeat the experiment with the paper folded into a tight ball and compare results
- Discuss how air resistance affects the paper but not the stone and relate to vacuum conditions

Why do skydivers open parachutes to slow their fall rather than falling freely to the ground?

- Humming Bird General Science Learner's Book pg. 283
- Stone, paper, writing materials
- Digital resources

- Observation - Oral questions

Natural Physical Science

Linear Motion -Tick timer investigation
Linear Motion -Free fall calculations

By the end of the lesson, the learner should be able to:
- Describe how a tick timer is used to investigate motion
- Analyse ticker tape results to determine velocity and acceleration
- Relate ticker tape analysis to how speed cameras and data loggers record vehicle motion
- Apply free fall equations v = gt and h = ½gt² to solve numerical problems
- Calculate velocity, height and time for freely falling bodies
- Relate free fall calculations to real-life situations such as objects falling from buildings and cliff heights

In groups, learners are guided to:
- Set up a ramp using books and cardboard and release different objects such as a marble, toy car, apple and pumpkin
- Observe and record how speed increases from rest to maximum at the bottom
- Analyse speed-time data from a table and calculate acceleration due to gravity
- Solve problems involving objects dropped from heights using v = gt and h = ½gt²
- Work through examples including construction workers dropping bricks and iron balls falling off cliffs
- Discuss how the acceleration due to gravity g = 10 m/s² is used in all free fall problems

How do engineers use motion sensors and data loggers to monitor the speed of vehicles during crash testing?
How do forensic investigators use free fall calculations to determine from what height an object fell at a crime scene?

- Humming Bird General Science Learner's Book pg. 285
- Cardboard, books, toy car, marble, apple
- Stopwatch, ruler
- Humming Bird General Science Learner's Book pg. 287
- Calculator
- Reference books

- Observation - Written assignments
- Written assignments - Oral questions

Natural Physical Science

Linear Motion -Safety on slopes

By the end of the lesson, the learner should be able to:
- Explain the dangers of accelerating on steeply sloping roads
- Identify safety measures used to minimise injuries from free fall and steep slopes
- Relate knowledge of free fall and acceleration to road safety practices such as speed limits and guardrails on hills

In groups, learners are guided to:
- Study pictures showing dangers of accelerating on sloping surfaces
- Discuss dangers including brake failure, traction loss and vehicles toppling on tight corners
- Discuss safety measures including harnesses on construction sites, parachutes in skydiving and seat belts in aircraft

Why are trucks required to use low gears and engine braking when descending steep mountain roads?

- Humming Bird General Science Learner's Book pg. 288
- Digital resources
- Pictures of road accidents on slopes

- Oral questions - Observation

Natural Physical Science

Linear Motion -Real-life applications of linear motion

By the end of the lesson, the learner should be able to:
- Identify real-life applications of linear motion including vehicles, elevators, sliding doors and projectiles
- Explain how linear motion principles apply to each example
- Relate linear motion to everyday technology such as lifts, sliding doors and bullet travel

In groups, learners are guided to:
- Study pictures showing applications of linear motion in different scenarios
- Discuss how vehicles, desk drawers, elevators and sliding doors all exhibit rectilinear motion
- Present findings in a plenary session

How does an elevator use the principles of linear motion to safely move passengers between floors of a building?

- Humming Bird General Science Learner's Book pg. 281
- Digital resources
- Internet access

- Oral questions - Observation

Natural Physical Science

Linear Motion -Real-life applications of linear motion

By the end of the lesson, the learner should be able to:
- Identify real-life applications of linear motion including vehicles, elevators, sliding doors and projectiles
- Explain how linear motion principles apply to each example
- Relate linear motion to everyday technology such as lifts, sliding doors and bullet travel

In groups, learners are guided to:
- Study pictures showing applications of linear motion in different scenarios
- Discuss how vehicles, desk drawers, elevators and sliding doors all exhibit rectilinear motion
- Present findings in a plenary session

How does an elevator use the principles of linear motion to safely move passengers between floors of a building?

- Humming Bird General Science Learner's Book pg. 281
- Digital resources
- Internet access

- Oral questions - Observation

Natural Physical Science

Waves -Amplitude and wavelength

By the end of the lesson, the learner should be able to:
- Define amplitude and wavelength and state their SI units
- Identify amplitude and wavelength on diagrams of transverse and longitudinal waves
- Relate amplitude and wavelength to real-life examples such as sound loudness and radio signal range

In groups, learners are guided to:
- Study diagrams of transverse waves and identify crests, troughs, amplitude and wavelength
- Use print or non-print media to research on terms used in waves
- Draw and label wave diagrams showing amplitude and wavelength

How does increasing the amplitude of a sound wave affect how loud the sound appears to a listener?

- Humming Bird General Science Learner's Book pg. 314
- Digital resources
- Wave diagrams, rulers

- Oral questions - Observation

Natural Physical Science

Waves -Frequency and period

By the end of the lesson, the learner should be able to:
- Define frequency and period and state their SI units
- Relate frequency and period using the equation T = 1/f
- Relate frequency and period to real-life applications such as radio broadcasting frequencies and musical notes

In groups, learners are guided to:
- Study displacement-time graphs and identify the period of a wave
- Calculate frequency from period and vice versa using T = 1/f
- Discuss examples such as radio stations broadcasting at specific frequencies

Why do radio stations broadcast at specific frequencies and what would happen if two stations used the same frequency?

- Humming Bird General Science Learner's Book pg. 315
- Digital resources
- Wave diagrams, calculator

- Oral questions - Written assignments

Natural Physical Science

Waves -Velocity of waves

By the end of the lesson, the learner should be able to:
- Define the velocity of a wave and state its SI unit
- Describe how wave velocity is related to the medium through which the wave travels
- Relate wave velocity to everyday phenomena such as the speed of sound in air and the speed of light

In groups, learners are guided to:
- Discuss the meaning of wave velocity as the distance a wave travels per second
- Compare the speed of sound in different media (air, water, solids)
- Discuss why lightning is seen before thunder is heard during a storm

Why do you see lightning before hearing thunder even though both are produced at the same time?

- Humming Bird General Science Learner's Book pg. 316
- Digital resources
- Reference books

- Oral questions - Observation

Natural Physical Science

Waves -Wave equation

By the end of the lesson, the learner should be able to:
- State the wave equation v = fλ
- Explain the relationship between wave speed, frequency and wavelength
- Relate the wave equation to real-life applications such as radio wave transmission and sonar

In groups, learners are guided to:
- Stretch a long rope on a flat surface and oscillate it to create waves
- Measure wavelength by marking distance between successive crests
- Count waves passing a fixed point in 10 seconds to find frequency and use v = fλ to calculate wave speed

How do telecommunications engineers use the wave equation to determine the wavelength of signals transmitted by mobile phone towers?

- Humming Bird General Science Learner's Book pg. 317
- Long rope, stopwatch, ruler
- Digital resources

- Observation - Oral questions

Natural Physical Science

Waves -Calculations using wave equation

By the end of the lesson, the learner should be able to:
- Apply the wave equation v = fλ to calculate wave speed, frequency or wavelength
- Solve numerical problems using the wave equation and displacement-time graphs
- Relate wave equation calculations to real-life contexts such as radio station broadcasting and sonar depth measurement

In groups, learners are guided to:
- Solve numerical problems using v = fλ involving sound and radio waves
- Determine amplitude, frequency and wavelength from displacement-time graphs
- Work through mixed problems and compare solutions with peers

How would a radio engineer calculate the wavelength of a broadcast signal given its frequency and the speed of radio waves?

- Humming Bird General Science Learner's Book pg. 318
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Waves -Calculations using wave equation

By the end of the lesson, the learner should be able to:
- Apply the wave equation v = fλ to calculate wave speed, frequency or wavelength
- Solve numerical problems using the wave equation and displacement-time graphs
- Relate wave equation calculations to real-life contexts such as radio station broadcasting and sonar depth measurement

In groups, learners are guided to:
- Solve numerical problems using v = fλ involving sound and radio waves
- Determine amplitude, frequency and wavelength from displacement-time graphs
- Work through mixed problems and compare solutions with peers

How would a radio engineer calculate the wavelength of a broadcast signal given its frequency and the speed of radio waves?

- Humming Bird General Science Learner's Book pg. 318
- Calculator
- Reference books

- Written assignments - Oral questions

Natural Physical Science

Waves -Reflection of sound and echo
Waves -Refraction of sound

By the end of the lesson, the learner should be able to:
- Define reflection of waves and explain how echoes are formed
- Calculate the speed of sound using the echo method
- Relate reflection of sound to real-life applications such as sonar, ultrasound scanning and echo-location in bats
- Define refraction of waves and explain how sound bends when passing through layers of air at different temperatures
- Distinguish between the behaviour of sound during the day and at night
- Relate refraction of sound to real-life phenomena such as distant sounds being louder at night and fog horns on ships

In groups, learners are guided to:
- Stand at a known distance from a large hard wall, clap hands and measure the time for the echo to return
- Calculate speed of sound using speed = 2d/t
- Repeat the experiment several times and calculate average speed of sound in air
- Watch videos on the behaviour of sound during the day and at night using a digital device
- Create two illustrations showing how sound waves bend upward during the day and downward at night
- Discuss how temperature differences in the atmosphere cause refraction

How do ships use sonar to detect underwater objects by reflecting sound waves off the seabed?
Why do sounds from a distant factory seem louder at night than during the day even though the factory operates at the same intensity?

- Humming Bird General Science Learner's Book pg. 320
- Stopwatch, measuring tape, hard wall
- Calculator
- Humming Bird General Science Learner's Book pg. 322
- Digital devices with internet access
- Drawing materials

- Observation - Written assignments
- Observation - Oral questions

Natural Physical Science

Waves -Diffraction of sound

By the end of the lesson, the learner should be able to:
- Define diffraction and explain how sound bends around obstacles and through openings
- Investigate how sound can be heard around a corner or through a slightly open door
- Relate diffraction to real-life situations such as hearing vehicles approaching around a blind corner

In groups, learners are guided to:
- Position a ringing phone behind a wall and check whether a listener on the other side can hear it
- Repeat with a slightly open door and note how sound spreads through the opening
- Discuss how diffraction allows sound to bend around edges and through gaps

How does diffraction of sound help a pedestrian hear an approaching vehicle before it comes into view around a corner?

- Humming Bird General Science Learner's Book pg. 323
- Phone, large wall, door
- Measuring tape

- Observation - Oral questions

Natural Physical Science

Waves -Diffraction of sound

By the end of the lesson, the learner should be able to:
- Define diffraction and explain how sound bends around obstacles and through openings
- Investigate how sound can be heard around a corner or through a slightly open door
- Relate diffraction to real-life situations such as hearing vehicles approaching around a blind corner

In groups, learners are guided to:
- Position a ringing phone behind a wall and check whether a listener on the other side can hear it
- Repeat with a slightly open door and note how sound spreads through the opening
- Discuss how diffraction allows sound to bend around edges and through gaps

How does diffraction of sound help a pedestrian hear an approaching vehicle before it comes into view around a corner?

- Humming Bird General Science Learner's Book pg. 323
- Phone, large wall, door
- Measuring tape

- Observation - Oral questions

Natural Physical Science

Waves -Effects of waves on the environment

By the end of the lesson, the learner should be able to:
- Explain how sound waves affect communities, marine ecosystems and infrastructure
- Describe the impact of noise pollution on human health, wildlife and buildings
- Relate the effects of waves on the environment to real-life issues such as factory noise, ship engines and bridge vibrations

In groups, learners are guided to:
- Study pictures of factories, traffic and ships and discuss their noise effects on communities and marine life
- Discuss how loud ship engines disrupt whale communication and how vibrations damage buildings
- Write short notes on the effects of sound waves on communities, marine ecosystems, infrastructure and operations

How do loud ship engines and underwater sonar systems used for navigation affect the communication and behaviour of whales?

- Humming Bird General Science Learner's Book pg. 325
- Digital resources
- Pictures of industrial and marine environments

- Oral questions - Observation

Natural Physical Science

Waves -Mitigation measures against effects of waves
Waves -Applications in road safety, refraction and diffraction

By the end of the lesson, the learner should be able to:
- Describe mitigation measures used to reduce the effects of waves on communities, marine ecosystems, infrastructure and operations
- Evaluate the effectiveness of sound barriers, earmuffs and marine protected areas in reducing noise pollution
- Relate mitigation strategies to decisions made by governments, urban planners and industries
- Explain how reflection, refraction and diffraction of sound waves contribute to road safety
- Describe how emergency sirens use wave properties to warn road users
- Relate wave properties to road safety systems such as sirens, fog horns and sound-based warning devices

In groups, learners are guided to:
- Walk around roads near residential areas and observe how windows, walls and doors are designed to reduce noise
- Discuss measures such as soundproof windows, noise barriers along roads, quieter ship engines and rubber pads on railway tracks
- Discuss other ways to reduce noise pollution and compare ideas with classmates
- Study diagrams showing how reflection, refraction and diffraction are applied in road safety
- Discuss how a motorcycle engine sound bends around a corner to warn pedestrians before the vehicle is visible
- Discuss how emergency sirens use reflection to be heard around obstacles and refraction to travel farther in cold weather

How do city planners use sound walls and zoning laws to protect residents from the noise of nearby industrial areas?
How does the diffraction of sound from a vehicle horn help a pedestrian at a blind junction react in time to avoid an accident?

- Humming Bird General Science Learner's Book pg. 327
- Digital resources
- Internet access
- Humming Bird General Science Learner's Book pg. 331
- Digital resources
- Internet access

- Oral questions - Observation
- Oral questions - Written assignments

Natural Physical Science

Waves -Applications in road safety, refraction and diffraction

By the end of the lesson, the learner should be able to:
- Explain how reflection, refraction and diffraction of sound waves contribute to road safety
- Describe how emergency sirens use wave properties to warn road users
- Relate wave properties to road safety systems such as sirens, fog horns and sound-based warning devices

In groups, learners are guided to:
- Study diagrams showing how reflection, refraction and diffraction are applied in road safety
- Discuss how a motorcycle engine sound bends around a corner to warn pedestrians before the vehicle is visible
- Discuss how emergency sirens use reflection to be heard around obstacles and refraction to travel farther in cold weather

How does the diffraction of sound from a vehicle horn help a pedestrian at a blind junction react in time to avoid an accident?

- Humming Bird General Science Learner's Book pg. 331
- Digital resources
- Internet access

- Oral questions - Written assignments

Natural Physical Science

Magnetism and Electromagnetic Induction -Magnetisation methods

By the end of the lesson, the learner should be able to:
- Describe the electrical, induction, stroking and hammering methods of magnetising soft iron
- Compare the strength and permanence of magnets produced by each method
- Relate magnetisation methods to real-life applications such as manufacturing compass needles, refrigerator door magnets and industrial lifting magnets

In groups, learners are guided to:
- Wrap insulated copper wire around a soft iron rod, connect to a battery and test with iron filings (electrical method)
- Place soft iron near a bar magnet without touching and test magnetism (induction method)
- Stroke a soft iron rod with a permanent magnet in one direction and test with iron filings (stroking method)
- Strike a soft iron rod aligned north-south with a hammer and test with iron filings (hammering method)

Which method of magnetisation would be most suitable for manufacturing a permanent compass needle and why?

- Humming Bird General Science Learner's Book pg. 338
- Soft iron rod, copper wire, battery, bar magnet, hammer, iron filings

- Observation - Oral questions

Natural Physical Science

Magnetism and Electromagnetic Induction -Demagnetisation

By the end of the lesson, the learner should be able to:
- Describe the electrical, hammering and heating methods of demagnetising a magnet
- Explain how each method disrupts the alignment of magnetic domains
- Relate demagnetisation to real-life situations such as erasing hotel key cards and resetting magnetic strips

In groups, learners are guided to:
- Wrap insulated copper wire around a magnetised soft iron rod, connect to AC power and test with iron filings after removing
- Strike a magnetised soft iron rod repeatedly with a hammer and test with iron filings
- Heat a magnetised soft iron rod until red-hot, allow to cool and test with iron filings
- Compare results of all three methods

Why must a magnet be oriented in the east-west direction during demagnetisation and what would happen if it were left pointing north-south?

- Humming Bird General Science Learner's Book pg. 344
- Magnetised soft iron rod, AC power source, hammer, Bunsen burner, tongs, iron filings

- Observation - Oral questions

Natural Physical Science

Magnetism and Electromagnetic Induction -Magnetic field patterns

By the end of the lesson, the learner should be able to:
- Describe magnetic field patterns around bar magnets, U-shaped magnets and horseshoe magnets
- Draw magnetic field lines showing direction from north to south pole and regions of attraction and repulsion
- Relate magnetic field patterns to real-life devices such as electric motors, MRI scanners and loudspeakers

In groups, learners are guided to:
- Place a bar magnet on a flat surface, cover with paper and sprinkle iron filings to reveal field pattern
- Use a small compass to trace field lines around the magnet marking direction of needle at each point
- Draw and compare field patterns around unlike poles (attraction) and like poles (repulsion)

How do the magnetic field patterns around a horseshoe magnet make it more effective for lifting metal objects than a straight bar magnet?

- Humming Bird General Science Learner's Book pg. 347
- Bar magnet, iron filings, white paper, small compass
- Drawing materials

- Observation - Oral questions

Natural Physical Science

Magnetism and Electromagnetic Induction -Direction and strength of fields

By the end of the lesson, the learner should be able to:
- Explain how the spacing and direction of magnetic field lines indicate field strength and direction
- Interpret magnetic field diagrams to identify regions of strong and weak fields
- Relate field strength and direction to real-life applications such as the design of speakers and electric motors

In groups, learners are guided to:
- Use compass results from the previous lesson to draw and interpret field line diagrams
- Identify regions near the poles where field lines are closest together as regions of strongest field
- Discuss with peers how field direction and density are used in the design of motors and generators

How does an engineer use knowledge of magnetic field strength and direction when designing the electromagnet in an electric motor?

- Humming Bird General Science Learner's Book pg. 348
- Bar magnet, compass, drawing materials
- Digital resources

- Observation - Oral questions

Natural Physical Science

Magnetism and Electromagnetic Induction -Induced EMF

By the end of the lesson, the learner should be able to:
- Define induced electromotive force (EMF) in electromagnetism
- State Faraday's law of electromagnetic induction
- Relate induced EMF to real-life devices such as bicycle dynamos, generators and transformers

In groups, learners are guided to:
- Use online resources or textbooks to research the meaning of induced EMF and Faraday's law
- Discuss how a changing magnetic field produces an EMF in a conductor
- Predict how a magnet's motion into a coil would affect a connected galvanometer

How does a bicycle dynamo use Faraday's law of electromagnetic induction to light the bicycle's headlamp without using batteries?

- Humming Bird General Science Learner's Book pg. 351
- Digital resources
- Reference books

- Oral questions - Observation

Natural Physical Science

Magnetism and Electromagnetic Induction -Induced EMF

By the end of the lesson, the learner should be able to:
- Define induced electromotive force (EMF) in electromagnetism
- State Faraday's law of electromagnetic induction
- Relate induced EMF to real-life devices such as bicycle dynamos, generators and transformers

In groups, learners are guided to:
- Use online resources or textbooks to research the meaning of induced EMF and Faraday's law
- Discuss how a changing magnetic field produces an EMF in a conductor
- Predict how a magnet's motion into a coil would affect a connected galvanometer

How does a bicycle dynamo use Faraday's law of electromagnetic induction to light the bicycle's headlamp without using batteries?

- Humming Bird General Science Learner's Book pg. 351
- Digital resources
- Reference books

- Oral questions - Observation

Natural Physical Science

Magnetism and Electromagnetic Induction -Practical demonstration
Magnetism and Electromagnetic Induction -Factors affecting induced EMF

By the end of the lesson, the learner should be able to:
- Perform an experiment to demonstrate electromagnetic induction using a U-shaped magnet, galvanometer and straight conductor
- Observe and explain the effect of direction and speed of conductor movement on the galvanometer reading
- Relate the experiment results to how generators and dynamos produce electricity in power stations
- Identify and explain the factors that affect the magnitude of induced EMF
- Describe how magnetic field strength, speed of motion, number of coil turns, angle of motion and type of material affect induced EMF
- Relate factors affecting induced EMF to the design of power generators in hydroelectric and wind power stations

In groups, learners are guided to:
- Connect a straight conductor to a galvanometer using connecting wires
- Position the conductor between the poles of a U-shaped magnet and move it up, down, parallel and at an angle
- Observe the galvanometer deflection in each case and record findings
- Use digital devices or print media to research on factors affecting the magnitude of induced EMF
- Discuss a case scenario of a school hydropower generator with reduced output during dry seasons
- Identify which EMF factors could be adjusted to increase power output and discuss with peers

How does the direction of movement of the coil in a generator determine the direction of the current supplied to homes and industries?
How would a hydroelectric power station engineer increase the electricity output of a generator during a dry season when water flow is reduced?

- Humming Bird General Science Learner's Book pg. 352
- U-shaped magnet, galvanometer, straight conductor, connecting wires
- Humming Bird General Science Learner's Book pg. 354
- Digital resources
- Reference books

- Observation - Written assignments
- Oral questions - Written assignments

Natural Physical Science

Magnetism and Electromagnetic Induction -Applications of electromagnetic induction

By the end of the lesson, the learner should be able to:
- Identify applications of electromagnetic induction in day-to-day life
- Explain how generators, transformers, induction cookers, wireless chargers and MRI scanners use electromagnetic induction
- Relate electromagnetic induction to familiar technologies such as wireless phone charging, induction cooktops and bicycle dynamos

In groups, learners are guided to:
- Study a presentation by peers on applications of electromagnetic induction
- Discuss how generators convert mechanical energy to electrical energy and how transformers step voltage up or down
- Research additional applications including induction cookers, MRI scanners, electric bells and magnetic card readers

How does the induction cooker in a modern kitchen use electromagnetic induction to heat a pot directly without heating the surface around it?

- Humming Bird General Science Learner's Book pg. 355
- Digital resources
- Internet access

- Oral questions - Observation

Natural Physical Science

Magnetism and Electromagnetic Induction -Applications of electromagnetic induction

By the end of the lesson, the learner should be able to:
- Identify applications of electromagnetic induction in day-to-day life
- Explain how generators, transformers, induction cookers, wireless chargers and MRI scanners use electromagnetic induction
- Relate electromagnetic induction to familiar technologies such as wireless phone charging, induction cooktops and bicycle dynamos

In groups, learners are guided to:
- Study a presentation by peers on applications of electromagnetic induction
- Discuss how generators convert mechanical energy to electrical energy and how transformers step voltage up or down
- Research additional applications including induction cookers, MRI scanners, electric bells and magnetic card readers

How does the induction cooker in a modern kitchen use electromagnetic induction to heat a pot directly without heating the surface around it?

- Humming Bird General Science Learner's Book pg. 355
- Digital resources
- Internet access

- Oral questions - Observation

Natural Physical Science

Magnetism and Electromagnetic Induction -Electric bell project

By the end of the lesson, the learner should be able to:
- Design and assemble a simple electric bell using locally available materials
- Explain how the electromagnetic principle makes the bell ring when the circuit is closed
- Relate the electric bell to real-life applications of electromagnets such as doorbells, relays and alarm systems

In groups, learners are guided to:
- Assemble an electric bell using a buzzer, battery, copper wire, iron nail, paperclip switch and plastic box
- Connect the circuit so that closing the switch causes the electromagnet to attract the hammer and strike the bell
- Test and troubleshoot the bell and present the working model to the class

How does the automatic reset mechanism in an electric doorbell use the principle of electromagnetic induction to repeatedly ring without being pressed again?

- Humming Bird General Science Learner's Book pg. 358
- Buzzer, battery, copper wire, iron nail, paperclip, plastic box, insulated wire, glue, tape

- Observation - Model making