Measurements

Area - Area of a pentagon
Area - Area of a hexagon

By the end of the lesson, the learner should be able to:

- Define a regular pentagon
- Draw a regular pentagon and divide it into triangles
- Calculate the area of a regular pentagon

- Draw a regular pentagon of sides 4 cm using protractor (108° angles)
- Join vertices to the centre to form triangles
- Determine the height of one triangle
- Calculate area of one triangle then multiply by number of triangles
- Use alternative formula: ½ × perimeter × perpendicular height

How do we find the area of a pentagon?

- Master Mathematics Grade 9 pg. 85
- Rulers and protractors
- Compasses
- Graph paper
- Charts showing pentagons
- Compasses and rulers
- Protractors
- Manila paper
- Digital devices

- Observation - Oral questions - Written assignments

Measurements

Area - Surface area of triangular prisms

By the end of the lesson, the learner should be able to:

- Identify triangular prisms
- Sketch nets of triangular prisms
- Calculate surface area of triangular prisms

- Identify differences between triangular and rectangular prisms
- Sketch nets of triangular prisms
- Identify all faces from the net
- Calculate area of each face
- Add all areas to get total surface area

How do we find the surface area of a triangular prism?

- Master Mathematics Grade 9 pg. 85
- Models of prisms
- Graph paper
- Rulers
- Reference materials

- Observation - Oral questions - Written assignments

Measurements

Area - Surface area of rectangular prisms
Area - Surface area of pyramids
Area - Surface area of square and rectangular pyramids

By the end of the lesson, the learner should be able to:

- Identify rectangular prisms (cuboids)
- Sketch nets of cuboids
- Calculate surface area of rectangular prisms

- Distinguish between square and rectangular based pyramids
- Apply Pythagoras theorem to find heights
- Calculate surface area of square and rectangular pyramids

- Sketch nets of rectangular prisms
- Identify pairs of equal rectangular faces
- Calculate area of each face
- Apply formula: 2(lw + lh + wh)
- Solve real-life problems involving cuboids
- Sketch nets of square and rectangular pyramids
- Use Pythagoras theorem to find perpendicular heights
- Calculate area of base
- Calculate area of each triangular face
- Apply formula: Base area + sum of triangular faces

How do we calculate the surface area of a cuboid?
How do we calculate surface area of different pyramids?

- Master Mathematics Grade 9 pg. 85
- Cuboid models
- Manila paper
- Scissors
- Calculators
- Sticks/straws
- Graph paper
- Protractors
- Reference books
- Master Mathematics Grade 9 pg. 85
- Graph paper
- Calculators
- Pyramid models
- Charts

- Observation - Oral questions - Written tests

Measurements

Area - Area of sectors of circles
Area - Area of segments of circles

By the end of the lesson, the learner should be able to:

- Define a sector of a circle
- Distinguish between major and minor sectors
- Calculate area of sectors using the formula

- Draw a circle and mark a clock face
- Identify sectors formed by clock hands
- Derive formula: Area = (θ/360) × πr²
- Calculate areas of sectors with different angles
- Use digital devices to watch videos on sectors

How do we find the area of a sector?

- Master Mathematics Grade 9 pg. 85
- Compasses and rulers
- Protractors
- Digital devices
- Internet access
- Compasses
- Rulers
- Calculators
- Graph paper

- Observation - Oral questions - Written assignments

Measurements

Area - Surface area of cones

By the end of the lesson, the learner should be able to:

- Define a cone and identify its parts
- Derive the formula for curved surface area
- Calculate surface area of solid cones

- Draw and cut a circle from manila paper
- Divide into two parts and fold to make a cone
- Identify slant height and radius
- Derive formula: πrl for curved surface
- Calculate total surface area: πrl + πr²
- Solve practical problems

How do we find the surface area of a cone?

- Master Mathematics Grade 9 pg. 85
- Manila paper
- Scissors
- Compasses and rulers
- Reference materials

- Observation - Oral questions - Written assignments

Measurements

Area - Surface area of spheres and hemispheres
Volume - Volume of triangular prisms

By the end of the lesson, the learner should be able to:

- Define a sphere and hemisphere
- Derive the formula for surface area of a sphere
- Calculate surface area of spheres and hemispheres

- Get a spherical ball and rectangular paper
- Cover ball with paper to form open cylinder
- Measure diameter and compare to height
- Derive formula: 4πr²
- Calculate surface area of hemispheres: 3πr²
- Solve real-life problems

How do we calculate the surface area of a sphere?

- Master Mathematics Grade 9 pg. 85
- Spherical balls
- Rectangular paper
- Rulers
- Calculators
- Master Mathematics Grade 9 pg. 102
- Straws and paper
- Sand or soil
- Measuring tools
- Reference books

- Observation - Oral questions - Written tests

Measurements

Volume - Volume of rectangular prisms
Volume - Volume of square-based pyramids
Volume - Volume of rectangular-based pyramids

By the end of the lesson, the learner should be able to:

- Identify rectangular prisms (cuboids)
- Apply the volume formula for cuboids
- Solve problems involving rectangular prisms

- Define a right pyramid
- Relate pyramid volume to cube volume
- Calculate volume of square-based pyramids

- Identify that cuboids are prisms with rectangular cross-section
- Apply formula: V = l × w × h
- Calculate volumes with different measurements
- Solve real-life problems (water tanks, dump trucks)
- Convert between cubic units
- Model a cube and pyramid with same base and height
- Fill pyramid with soil and transfer to cube
- Observe that pyramid is ⅓ of cube
- Apply formula: V = ⅓ × base area × height
- Calculate volumes of square-based pyramids

How do we calculate the volume of a cuboid?
How do we find the volume of a pyramid?

- Master Mathematics Grade 9 pg. 102
- Cuboid models
- Calculators
- Charts
- Reference materials
- Master Mathematics Grade 9 pg. 102
- Modeling materials
- Soil or sand
- Rulers
- Calculators
- Pyramid models
- Graph paper
- Reference books

- Observation - Oral questions - Written tests
- Observation - Oral questions - Written assignments

Measurements

Volume - Volume of triangular-based pyramids

By the end of the lesson, the learner should be able to:

- Calculate area of triangular bases
- Apply Pythagoras theorem where necessary
- Calculate volume of triangular-based pyramids

- Calculate area of triangular base (using ½bh)
- For equilateral triangles, use Pythagoras to find height
- Apply formula: V = ⅓ × (½bh) × H
- Solve problems with different triangular bases

How do we find volume of triangular pyramids?

- Master Mathematics Grade 9 pg. 102
- Triangular pyramid models
- Rulers
- Calculators
- Charts

- Observation - Oral questions - Written assignments

Measurements

Volume - Introduction to volume of cones
Volume - Calculating volume of cones

By the end of the lesson, the learner should be able to:

- Define a cone as a circular-based pyramid
- Relate cone volume to cylinder volume
- Derive the volume formula for cones

- Model a cylinder and cone with same radius and height
- Fill cone with water and transfer to cylinder
- Observe that cone is ⅓ of cylinder
- Derive formula: V = ⅓πr²h
- Use digital devices to watch videos

How is a cone related to a cylinder?

- Master Mathematics Grade 9 pg. 102
- Cone and cylinder models
- Water
- Digital devices
- Internet access
- Cone models
- Calculators
- Graph paper
- Reference materials

- Observation - Oral questions - Written tests

Measurements

Volume - Volume of frustums of pyramids

By the end of the lesson, the learner should be able to:

- Define a frustum
- Explain how to obtain a frustum
- Calculate volume of frustums of pyramids

- Model a pyramid and cut it parallel to base
- Identify the frustum formed
- Calculate volume of original pyramid
- Calculate volume of small pyramid cut off
- Apply formula: Volume of frustum = V(large) - V(small)

What is a frustum and how do we find its volume?

- Master Mathematics Grade 9 pg. 102
- Pyramid models
- Cutting tools
- Rulers
- Calculators

- Observation - Oral questions - Written tests

Measurements

Volume - Volume of frustums of cones
Volume - Volume of spheres
Volume - Volume of hemispheres and applications
Mass, Volume, Weight and Density - Conversion of units of mass

By the end of the lesson, the learner should be able to:

- Identify frustums of cones
- Apply the frustum concept to cones
- Calculate volume of frustums of cones

- Define a hemisphere
- Calculate volume of hemispheres
- Solve real-life problems involving volumes

- Identify frustums with circular bases
- Calculate volume of original cone
- Calculate volume of small cone cut off
- Subtract to get volume of frustum
- Solve real-life problems (lampshades, buckets)
- Apply formula: V = ½ × 4/3πr³ = 2/3πr³
- Calculate volumes of hemispheres
- Solve problems involving spheres and hemispheres
- Apply to real situations (bowls, domes, balls)

How do we calculate the volume of a frustum of a cone?
How do we calculate the volume of a hemisphere?

- Master Mathematics Grade 9 pg. 102
- Cone models
- Frustum examples
- Calculators
- Reference books
- Hollow spheres
- Water or soil
- Master Mathematics Grade 9 pg. 102
- Hemisphere models
- Calculators
- Real objects
- Reference materials
- Master Mathematics Grade 9 pg. 111
- Weighing balances
- Various objects
- Conversion charts

- Observation - Oral questions - Written assignments

Measurements

Mass, Volume, Weight and Density - More practice on mass conversions

By the end of the lesson, the learner should be able to:

- Convert masses to kilograms
- Apply conversions in real-life contexts
- Appreciate the importance of mass measurements

- Convert various masses to kilograms
- Work with large masses (tonnes)
- Work with small masses (milligrams, micrograms)
- Solve practical problems (construction, medicine, shopping)

Why is it important to convert units of mass?

- Master Mathematics Grade 9 pg. 111
- Conversion tables
- Calculators
- Real-world examples
- Reference books

- Observation - Oral questions - Written assignments

Measurements

Mass, Volume, Weight and Density - Relationship between mass and weight
Mass, Volume, Weight and Density - Calculating mass and gravity

By the end of the lesson, the learner should be able to:

- Define weight and state its SI unit
- Distinguish between mass and weight
- Calculate weight from mass using gravity

- Study spring balance showing both mass and weight
- Observe relationship: 1 kg = 10 N
- Apply formula: Weight = mass × gravity
- Calculate weights of various objects
- Understand that mass is constant but weight varies

What is the difference between mass and weight?

- Master Mathematics Grade 9 pg. 111
- Spring balances
- Various objects
- Charts
- Calculators
- Charts showing planetary data
- Reference materials
- Digital devices

- Observation - Oral questions - Written tests

Measurements

Mass, Volume, Weight and Density - Introduction to density

By the end of the lesson, the learner should be able to:

- Define density
- State units of density
- Relate mass, volume and density

- Weigh empty container
- Measure volume of water using measuring cylinder
- Weigh container with water
- Calculate mass of water
- Divide mass by volume to get density
- Apply formula: Density = Mass/Volume

What is density?

- Master Mathematics Grade 9 pg. 111
- Weighing balances
- Measuring cylinders
- Water
- Containers
- Calculators

- Observation - Oral questions - Written tests

Measurements

Mass, Volume, Weight and Density - Calculating density, mass and volume
Mass, Volume, Weight and Density - Applications of density
Time, Distance and Speed - Working out speed in km/h and m/s

By the end of the lesson, the learner should be able to:

- Apply density formula to find density
- Calculate mass using density formula
- Calculate volume using density formula

- Define speed
- Calculate speed in km/h
- Calculate speed in m/s
- Convert between km/h and m/s

- Apply formula: D = M/V to find density
- Rearrange to find mass: M = D × V
- Rearrange to find volume: V = M/D
- Convert between g/cm³ and kg/m³
- Solve various problems
- Go to field and mark two points 100 m apart
- Measure distance between points
- Time a person running between points
- Calculate speed: Speed = Distance/Time
- Calculate speed in m/s using metres and seconds
- Convert distance to kilometers and time to hours
- Calculate speed in km/h
- Convert km/h to m/s (divide by 3.6)
- Convert m/s to km/h (multiply by 3.6)

How do we use the density formula?
How do we calculate speed in different units?

- Master Mathematics Grade 9 pg. 111
- Calculators
- Charts with formulas
- Various solid objects
- Reference books
- Density tables
- Real-world scenarios
- Reference materials
- Master Mathematics Grade 9 pg. 117
- Stopwatches
- Tape measures
- Open field
- Calculators
- Conversion charts

- Observation - Oral questions - Written assignments

Measurements

Time, Distance and Speed - Calculating distance and time from speed
Time, Distance and Speed - Working out average speed

By the end of the lesson, the learner should be able to:

- Rearrange speed formula to find distance
- Rearrange speed formula to find time
- Solve problems involving speed, distance and time
- Apply to real-life situations

- Apply formula: Distance = Speed × Time
- Apply formula: Time = Distance/Speed
- Solve problems with different units
- Apply to journeys, races, train travel
- Work with Madaraka Express train problems
- Calculate distances covered at given speeds
- Calculate time taken for journeys

How do we calculate distance and time from speed?

- Master Mathematics Grade 9 pg. 117
- Calculators
- Formula charts
- Real-world examples
- Reference materials
- Field with marked points
- Stopwatches
- Reference books

- Observation - Oral questions - Written tests

Measurements

Time, Distance and Speed - Determining velocity

By the end of the lesson, the learner should be able to:

- Define velocity
- Distinguish between speed and velocity
- Calculate velocity with direction
- Appreciate the importance of direction in velocity

- Define velocity as speed in a given direction
- Identify that velocity includes direction
- Calculate velocity for objects moving in straight lines
- Understand that velocity can be positive or negative
- Understand that same speed in opposite directions means different velocities
- Apply to real situations involving directional movement

What is the difference between speed and velocity?

- Master Mathematics Grade 9 pg. 117
- Diagrams showing direction
- Calculators
- Charts
- Reference materials

- Observation - Oral questions - Written tests

Measurements

Time, Distance and Speed - Working out acceleration
Time, Distance and Speed - Deceleration and applications

By the end of the lesson, the learner should be able to:

- Define acceleration
- Calculate acceleration from velocity changes
- Apply acceleration formula
- State units of acceleration (m/s²)
- Identify situations involving acceleration

- Walk from one point then run to another point
- Calculate velocity for each section
- Find difference in velocities (change in velocity)
- Define acceleration as rate of change of velocity
- Apply formula: a = (v - u)/t where v=final velocity, u=initial velocity, t=time
- Calculate acceleration when starting from rest (u=0)
- Calculate acceleration with initial velocity
- State that acceleration is measured in m/s²
- Identify real-life examples of acceleration

What is acceleration and how do we calculate it?

- Master Mathematics Grade 9 pg. 117
- Field for activity
- Stopwatches
- Measuring tools
- Calculators
- Formula charts
- Road safety materials
- Charts
- Reference materials

- Observation - Oral questions - Written assignments

Measurements

Time, Distance and Speed - Identifying longitudes on the globe
Time, Distance and Speed - Relating longitudes to time
Time, Distance and Speed - Calculating time differences between places

By the end of the lesson, the learner should be able to:

- Identify longitudes on a globe
- Distinguish between latitudes and longitudes
- Use atlas to find longitudes of places
- State longitudes of various towns and cities

- Explain relationship between longitudes and time
- State that Earth rotates 360° in 24 hours
- Calculate that 1° = 4 minutes
- Understand time zones and GMT

- Study globe showing longitudes and latitudes
- Identify that longitudes run North to South (meridians)
- Identify that latitudes run East to West
- Identify Greenwich Meridian (0°)
- Use atlas to find longitudes of various places
- Distinguish between East and West longitudes
- Find longitudes of towns in Kenya, Africa, and world map
- Identify islands at specific longitudes
- Understand Earth rotates 360° in 24 hours
- Calculate: 360° = 24 hours = 1440 minutes
- Therefore: 1° = 4 minutes
- Identify time zones on world map
- Understand GMT (Greenwich Mean Time)
- Learn that places East of Greenwich are ahead in time
- Learn that places West of Greenwich are behind in time
- Use digital devices to check time zones

What are longitudes and how do we identify them?
How are longitudes related to time?

- Master Mathematics Grade 9 pg. 117
- Globes
- Atlases
- World maps
- Charts
- Master Mathematics Grade 9 pg. 117
- Globes
- Time zone maps
- Calculators
- Digital devices
- Atlases
- Time zone charts
- Reference books

- Observation - Oral questions - Written assignments
- Observation - Oral questions - Written tests

Measurements

Time, Distance and Speed - Determining local time of places along different longitudes

By the end of the lesson, the learner should be able to:

- Calculate local time when given GMT or another place's time
- Add or subtract time differences appropriately
- Account for date changes
- Solve complex time zone problems
- Apply knowledge to real-life situations

- Calculate time difference from longitude difference
- Add time if place is East of reference point (ahead)
- Subtract time if place is West of reference point (behind)
- Account for date changes when crossing midnight
- Solve problems with GMT as reference
- Solve problems with other places as reference
- Apply to phone calls, soccer matches, travel planning
- Work backwards to find longitude from time difference
- Determine whether places are East or West from time relationships

How do we find local time at different longitudes?

- Master Mathematics Grade 9 pg. 117
- World maps
- Calculators
- Time zone references
- Atlases
- Real-world scenarios

- Observation - Oral questions - Written tests - Problem-solving tasks

Measurements

Money - Identifying currencies of different countries
Money - Converting foreign currency to Kenyan shillings

By the end of the lesson, the learner should be able to:

- Identify currencies used in different countries
- State the Kenyan currency and its abbreviation
- Match countries with their currencies
- Appreciate diversity in world currencies

- Use digital devices to search for pictures of currencies
- Identify currencies of Britain, Uganda, Tanzania, USA, Rwanda, South Africa
- Make a collage of currencies from African countries
- Complete tables matching countries with their currencies
- Study Kenya shilling and its subdivision into cents
- Discuss the importance of different currencies

What currencies are used in different countries?

- Master Mathematics Grade 9 pg. 131
- Digital devices
- Internet access
- Pictures of currencies
- Atlases
- Reference materials
- Currency conversion tables
- Calculators
- Charts

- Observation - Oral questions - Written assignments - Project work

Measurements

Money - Converting Kenyan shillings to foreign currency and buying/selling rates

By the end of the lesson, the learner should be able to:

- Convert Kenyan shillings to foreign currencies
- Distinguish between buying and selling rates
- Apply correct rates when converting currency
- Solve multi-step currency problems

- Convert Ksh to Ugandan shillings, Sterling pounds, Japanese Yen
- Study Table 3.5.2 showing buying and selling rates
- Understand that banks buy at lower rate, sell at higher rate
- Learn when to use buying rate (foreign to Ksh)
- Learn when to use selling rate (Ksh to foreign)
- Solve tourist problems with multiple conversions
- Visit commercial banks or Forex Bureaus

Why do buying and selling rates differ?

- Master Mathematics Grade 9 pg. 131
- Exchange rate tables
- Calculators
- Real-world scenarios
- Reference books

- Observation - Oral questions - Written assignments

Measurements

Money - Export duty on goods
Money - Import duty on goods
Money - Excise duty and Value Added Tax (VAT)

By the end of the lesson, the learner should be able to:

- Define export and export duty
- Explain the purpose of export duty
- Calculate product cost and export duty
- Solve problems on exported goods

- Define excise duty and VAT
- Identify goods subject to excise duty
- Calculate excise duty and VAT
- Distinguish between the two types of taxes

- Discuss goods Kenya exports to other countries
- Understand how Kenya benefits from exports
- Define product cost and its components
- Apply formula: Product cost = Unit cost × Quantity
- Apply formula: Export duty = Tax rate × Product cost
- Calculate export duty on flowers, tea, coffee, cement
- Discuss importance of increasing exports
- Search online for goods subject to excise duty
- Study excise duty rates for different commodities
- Apply formula: Excise duty = Tax rate × Excise value
- Study Electronic Tax Register (ETR) receipts
- Learn that VAT is charged at 16% at multiple stages
- Calculate VAT on purchases
- Apply both taxes to various goods and services

What is export duty and why is it charged?
What are excise duty and VAT?

- Master Mathematics Grade 9 pg. 131
- Calculators
- Examples of export goods
- Charts
- Reference materials
- Import duty examples
- Reference books
- Master Mathematics Grade 9 pg. 131
- Digital devices
- ETR receipts
- Tax rate tables
- Calculators
- Reference materials

- Observation - Oral questions - Written tests

Measurements

Money - Combined duties and taxes on imported goods
Approximations and Errors - Approximating quantities in measurements

By the end of the lesson, the learner should be able to:

- Calculate multiple taxes on imported goods
- Apply import duty, excise duty, and VAT sequentially
- Solve complex problems involving all taxes
- Appreciate the cumulative effect of taxes

- Calculate import duty first
- Calculate excise value: Customs value + Import duty
- Calculate excise duty on excise value
- Calculate VAT value: Customs value + Import duty + Excise duty
- Calculate VAT on VAT value
- Apply to vehicles, electronics, cement, phones
- Solve comprehensive taxation problems
- Work backwards to find customs value

How do we calculate total taxes on imported goods?

- Master Mathematics Grade 9 pg. 131
- Calculators
- Comprehensive examples
- Charts showing tax flow
- Reference materials
- Master Mathematics Grade 9 pg. 146
- Tape measures
- Various objects to measure
- Containers for capacity

- Observation - Oral questions - Written assignments

Measurements

Approximations and Errors - Determining errors using estimations and actual measurements

By the end of the lesson, the learner should be able to:

- Define error in measurement
- Calculate error using approximated and actual values
- Distinguish between positive and negative errors
- Appreciate the importance of accuracy

- Fill 500 ml bottle and measure actual volume
- Calculate difference between labeled and actual values
- Apply formula: Error = Approximated value - Actual value
- Work with errors in mass, length, volume, time
- Complete tables showing actual, estimated values and errors
- Apply to bread packages, water bottles, cement bags
- Discuss integrity in measurements

What is error and how do we calculate it?

- Master Mathematics Grade 9 pg. 146
- Measuring cylinders
- Water bottles
- Weighing scales
- Calculators
- Reference materials

- Observation - Oral questions - Written assignments

Measurements

Approximations and Errors - Calculating percentage error
Approximations and Errors - Percentage error in real-life situations

By the end of the lesson, the learner should be able to:

- Define percentage error
- Calculate percentage error from approximations
- Express error as a percentage of actual value
- Compare errors using percentages

- Make strides and estimate total distance
- Measure actual distance covered
- Calculate error: Estimated value - Actual value
- Apply formula: Percentage error = (Error/Actual value) × 100%
- Solve problems on pavement width
- Calculate percentage errors in various measurements
- Round answers appropriately

How do we calculate percentage error?

- Master Mathematics Grade 9 pg. 146
- Tape measures
- Calculators
- Open ground for activities
- Reference books
- Real-world scenarios
- Case studies
- Reference materials

- Observation - Oral questions - Written tests

Measurements
4.0 Geometry

Approximations and Errors - Complex applications and problem-solving
4.1 Coordinates and Graphs - Plotting points on a Cartesian plane
4.1 Coordinates and Graphs - Drawing straight line graphs given equations
4.1 Coordinates and Graphs - Drawing parallel lines on the Cartesian plane
4.1 Coordinates and Graphs - Relating gradients of parallel lines

By the end of the lesson, the learner should be able to:

- Solve complex problems involving percentage errors
- Apply error calculations to budgeting and planning
- Evaluate the impact of errors
- Emphasize honesty and integrity in approximations

- Explain the steps for generating a table of values from an equation
- Draw straight line graphs accurately from linear equations
- Appreciate the relationship between equations and graphs

- Calculate percentage errors in fuel consumption estimates
- Work on budget estimation errors (school fuel budgets)
- Solve problems on athlete timing and weight
- Apply to construction cost estimates
- Analyze large errors and their consequences
- Discuss ways to minimize errors
- Emphasize ethical considerations in approximations
- Solve comprehensive review problems
The learner is guided to:
- Generate a table of values for given linear equations
- Plot the points on a Cartesian plane
- Draw straight lines passing through the plotted points
- Share and discuss their working with other members in class

How can we minimize errors and ensure accuracy?
How do we represent linear equations graphically?

- Master Mathematics Grade 9 pg. 146
- Calculators
- Complex scenarios
- Charts
- Reference books
- Real-world case studies
- Master Mathematics Grade 9 pg. 152
- Graph papers/squared books
- Rulers
- Pencils
- Digital devices
- Master Mathematics Grade 9 pg. 154
- Graph papers
- Rulers
- Pencils
- Mathematical tables
- Master Mathematics Grade 9 pg. 156
- Set squares
- Master Mathematics Grade 9 pg. 158
- Calculators
- Digital devices

- Observation - Oral questions - Written tests - Project work

4.0 Geometry

4.1 Coordinates and Graphs - Drawing perpendicular lines on the Cartesian plane
4.1 Coordinates and Graphs - Relating gradients of perpendicular lines and applications
4.2 Scale Drawing - Compass bearing

By the end of the lesson, the learner should be able to:

- Explain the meaning of perpendicular lines
- Draw and measure angles between perpendicular lines accurately
- Show interest in recognizing perpendicular lines from their graphs

The learner is guided to:
- Draw straight lines on the same Cartesian plane
- Identify the point where the two lines intersect
- Measure the angle between the two lines at the point of intersection
- Verify that perpendicular lines intersect at 90°

How do we identify perpendicular lines on a graph?

- Master Mathematics Grade 9 pg. 160
- Graph papers
- Protractors
- Rulers
- Set squares
- Master Mathematics Grade 9 pg. 162
- Calculators
- Real-life graph examples
- Master Mathematics Grade 9 pg. 166
- Pair of compasses
- Charts showing compass directions

- Observation - Class activities - Written tests

4.0 Geometry

4.2 Scale Drawing - True bearings
4.2 Scale Drawing - Determining the bearing of one point from another (1)

By the end of the lesson, the learner should be able to:

- Explain what true bearings are
- Convert compass bearings to true bearings and measure them accurately
- Appreciate expressing direction using true bearings

The learner is guided to:
- Discuss that true bearings are measured clockwise from North
- Express bearings in three-digit format
- Draw diagrams showing true bearings
- Convert between compass and true bearings

How do we express direction using true bearings?

- Master Mathematics Grade 9 pg. 169
- Protractors
- Rulers
- Compasses
- Map samples
- Master Mathematics Grade 9 pg. 171
- Pencils
- Graph papers

- Written tests - Class activities

4.0 Geometry

4.2 Scale Drawing - Determining the bearing of one point from another (2)
4.2 Scale Drawing - Locating a point using bearing and distance (1)

By the end of the lesson, the learner should be able to:

- State the bearing of places from maps
- Determine bearings from scale drawings and solve related problems
- Appreciate applying bearing concepts to real-life situations

The learner is guided to:
- Use maps of Kenya to determine bearings of different towns
- Work out bearings of points from given diagrams
- Determine reverse bearings
- Apply bearing concepts to real-life situations

Why is it important to know bearings in real life?

- Master Mathematics Grade 9 pg. 171
- Atlas/Maps of Kenya
- Protractors
- Rulers
- Digital devices
- Master Mathematics Grade 9 pg. 173
- Compasses
- Plain papers

- Class activities - Written tests

4.0 Geometry

4.2 Scale Drawing - Locating a point using bearing and distance (2)
4.2 Scale Drawing - Identifying angles of elevation (1)
4.2 Scale Drawing - Determining angles of elevation (2)

By the end of the lesson, the learner should be able to:

- Describe the process of locating points using bearing and distance
- Draw accurate scale diagrams and determine unknown measurements
- Appreciate the accuracy of scale drawings in representing real situations

- Explain the process of determining angles of elevation
- Draw scale diagrams and measure angles of elevation using protractors
- Appreciate applying concepts to real-life situations

The learner is guided to:
- Use given bearings and distances to locate points
- Draw accurate scale diagrams
- Measure and determine unknown distances and bearings from diagrams
- Verify accuracy of their drawings
The learner is guided to:
- Draw scale diagrams representing elevation situations
- Use appropriate scales
- Measure angles of elevation from scale drawings
- Solve problems involving heights and distances

How accurate are scale drawings in representing real situations?
How do we calculate angles of elevation?

- Master Mathematics Grade 9 pg. 173
- Rulers
- Protractors
- Compasses
- Graph papers
- Master Mathematics Grade 9 pg. 175
- Pictures showing elevation
- Models
- Master Mathematics Grade 9 pg. 175
- Protractors
- Rulers
- Graph papers
- Calculators

- Class activities - Written tests
- Written tests - Class activities

4.0 Geometry

4.2 Scale Drawing - Identifying angles of depression (1)
4.2 Scale Drawing - Determining angles of depression (2)

By the end of the lesson, the learner should be able to:

- Define angle of depression
- Identify and sketch situations involving angles of depression
- Show interest in distinguishing between angles of elevation and depression

The learner is guided to:
- Stand at elevated positions and observe objects below
- Identify the angle through which eyes are lowered
- Sketch right-angled triangles formed
- Label the angle of depression correctly

How is angle of depression different from angle of elevation?

- Master Mathematics Grade 9 pg. 178
- Protractors
- Rulers
- Pictures showing depression
- Models
- Graph papers
- Calculators

- Observation - Oral questions

4.0 Geometry

4.2 Scale Drawing - Application in simple surveying - Triangulation (1)

By the end of the lesson, the learner should be able to:

- Explain the concept of triangulation in surveying
- Identify baselines and offsets and draw diagrams using triangulation method
- Develop interest in using triangulation for surveying

The learner is guided to:
- Trace irregular shapes to be surveyed
- Enclose the shape with a triangle
- Identify and measure baselines
- Draw perpendicular offsets to the baselines

What is triangulation and how is it used in surveying?

- Master Mathematics Grade 9 pg. 180
- Rulers
- Set squares
- Compasses
- Plain papers

- Observation - Class activities

4.0 Geometry

4.2 Scale Drawing - Application in simple surveying - Triangulation (2)
4.2 Scale Drawing - Application in simple surveying - Transverse survey (1)

By the end of the lesson, the learner should be able to:

- Describe how to record measurements in field books
- Draw accurate scale maps using triangulation data
- Appreciate applying triangulation to survey school compound areas

The learner is guided to:
- Measure lengths of offsets
- Record measurements in field book format
- Choose appropriate scales
- Draw accurate scale maps from recorded data

How do we record and use surveying measurements?

- Master Mathematics Grade 9 pg. 180
- Meter rules
- Strings
- Pegs
- Field books
- Rulers
- Set squares
- Plain papers

- Written tests - Practical activities

4.0 Geometry
4.0 Geometry
5.0 Data Handling and Probability
5.0 Data Handling and Probability

4.2 Scale Drawing - Application in simple surveying - Transverse survey (2)
4.2 Scale Drawing - Surveying using bearings and distances
5.1 Data Interpretation (Grouped Data) - Determining appropriate class width for grouping data
5.1 Data Interpretation (Grouped Data) - Drawing frequency distribution tables of grouped data

By the end of the lesson, the learner should be able to:

- Describe the process of completing field books for transverse surveys
- Draw scale maps from transverse survey data
- Appreciate using transverse survey method for road reserves

- Explain how to record positions using bearings and distances
- Draw scale maps using bearing and distance data
- Appreciate different surveying methods

The learner is guided to:
- Complete field book recordings
- Use appropriate scales to draw maps
- Join offset points to show boundaries
- Compare their work with other members
The learner is guided to:
- Record bearings and distances from fixed points
- Use ordered pairs to represent positions
- Draw North lines and locate points using bearings
- Join points to show boundaries

When do we use transverse survey method?
How do we survey using bearings and distances?

- Master Mathematics Grade 9 pg. 180
- Rulers
- Pencils
- Graph papers
- Field books
- Master Mathematics Grade 9 pg. 180
- Protractors
- Compasses
- Rulers
- Field books
- Master Mathematics Grade 9 pg. 224
- Writing materials
- Calculators
- Chart papers
- Digital devices
- Master Mathematics Grade 9 pg. 226
- Tally sheets
- Data sets
- Pencils

- Written assignments - Practical activities
- Class activities - Written tests

5.0 Data Handling and Probability

5.1 Data Interpretation (Grouped Data) - Identifying the modal class of grouped data
5.1 Data Interpretation (Grouped Data) - Calculating the mean of grouped data (1)
5.1 Data Interpretation (Grouped Data) - Calculating the mean of grouped data (2)

By the end of the lesson, the learner should be able to:

- Define mode, modal frequency and modal class
- Identify the modal class from frequency distribution tables
- Appreciate identifying the class with highest frequency

The learner is guided to:
- Prepare frequency distribution tables for given data
- Identify the highest frequency from the table
- Find the class where the highest frequency lies
- Search for the meaning of mode using digital devices

What is the modal class in grouped data?

- Master Mathematics Grade 9 pg. 228
- Frequency distribution tables
- Digital devices
- Reference materials
- Master Mathematics Grade 9 pg. 230
- Calculators
- Frequency tables
- Writing materials
- Mathematical tables
- Data sets
- Charts

- Oral questions - Written assignments - Class activities

5.0 Data Handling and Probability

5.1 Data Interpretation (Grouped Data) - Determining the median of grouped data (1)
5.1 Data Interpretation (Grouped Data) - Determining the median of grouped data (2)
5.1 Data Interpretation (Grouped Data) - Determining the median of grouped data (3)

By the end of the lesson, the learner should be able to:

- Define cumulative frequency
- Determine cumulative frequencies from frequency tables
- Show interest in understanding the median class

The learner is guided to:
- Search for the meaning of cumulative frequency
- Transfer first frequency to cumulative frequency column
- Add frequencies cumulatively in ascending order
- Identify the median class by finding N/2

What is cumulative frequency?

- Master Mathematics Grade 9 pg. 232
- Frequency tables
- Calculators
- Reference materials
- Digital devices
- Master Mathematics Grade 9 pg. 234
- Formula charts
- Master Mathematics Grade 9 pg. 236
- Data sets
- Writing materials
- Practice worksheets

- Observation - Written tests

5.0 Data Handling and Probability

5.2 Probability - Experiments involving equally and likely outcomes
5.2 Probability - Range of probability of an event

By the end of the lesson, the learner should be able to:

- Define equally likely outcomes
- Perform experiments to determine equally likely outcomes
- Appreciate that equally likely outcomes have equal chances of happening

The learner is guided to:
- Toss a coin and note the side facing up
- Predict and observe outcomes of coin tossing
- Discuss whether outcomes are predictable
- Work out probabilities using dice and other objects

What are equally likely outcomes?

- Master Mathematics Grade 9 pg. 239
- Coins
- Dice
- Triangular pyramids
- Baskets and pens
- Master Mathematics Grade 9 pg. 241
- Calculators
- Charts showing probability range

- Observation - Oral questions - Practical activities

5.0 Data Handling and Probability

5.2 Probability - Identifying mutually exclusive events
5.2 Probability - Experiments of single chance involving mutually exclusive events
5.2 Probability - Experiments involving independent events

By the end of the lesson, the learner should be able to:

- Define mutually exclusive events
- Identify mutually exclusive events from given situations
- Appreciate that mutually exclusive events cannot occur simultaneously

- Explain the addition law of probability P(A or B) = P(A) + P(B)
- Calculate probabilities of mutually exclusive events
- Show interest in applying the addition law to solve problems

The learner is guided to:
- Observe a coin toss and note that both sides cannot face up
- Discuss what the referee does before a football match
- Identify events that exclude each other
- Give examples of mutually exclusive events from daily life
The learner is guided to:
- Pick pens from a closed bag and note colors
- Work out probabilities using the word "OR"
- Apply the formula P(A or B) = P(A) + P(B)
- Solve problems involving mutually exclusive events

What are mutually exclusive events?
How do we calculate probabilities of mutually exclusive events?

- Master Mathematics Grade 9 pg. 243
- Coins
- Pictures of referees
- Real-life scenarios
- Charts
- Master Mathematics Grade 9 pg. 244
- Colored pens
- Bags
- Dice
- Number cards
- Calculators
- Master Mathematics Grade 9 pg. 246
- Coins
- Colored balls
- Baskets

- Observation - Oral questions - Written assignments
- Class activities - Written tests - Practical exercises

5.0 Data Handling and Probability

5.2 Probability - Drawing tree diagrams for single outcomes

By the end of the lesson, the learner should be able to:

- Explain what a tree diagram represents
- Draw tree diagrams showing probability outcomes on branches
- Show interest in verifying that sum of probabilities on branches equals 1

The learner is guided to:
- Identify possible outcomes from tossing a coin
- Draw branches and fill in outcomes
- Determine probabilities and place on branches
- Verify that sum of probabilities equals 1
- Draw tree diagrams for various probability situations

How do we represent probability using tree diagrams?

- Master Mathematics Grade 9 pg. 248
- Drawing materials
- Coins
- Calculators
- Chart papers
- Rulers

- Class activities - Written tests - Practical activities