Measurements

Area - Surface area of prisms
Area - Surface area of pyramids

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

- Identify the faces of triangular and rectangular-based prisms.
- Calculate the surface area of prisms by summing the areas of all faces using the formula 2(cross-section area) + (perimeter × length).
- Appreciate the relationship between surface area and material requirements in packaging and construction.

In groups, learners are guided to:

- Collect triangular-based prism models, open them to form nets and label all faces.
- Calculate the area of each face and add them together to find total surface area.
- Discuss and sketch nets of rectangular-based prisms, calculate the area of each face and sum.

How do we work out the area of different surfaces?

- Oxford Active Mathematics Grade 9 pg. 85
- Triangular and rectangular-based prism models
- Ruler, sheets of paper
- Oxford Active Mathematics Grade 9 pg. 87
- Pyramid models, sheets of paper, ruler

- Written assignments - Oral questions - Observation

Measurements

Area - Area of a sector and segment of a circle

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

- Define a sector and a segment of a circle and state the formulas used to calculate each.
- Calculate the area of a sector and segment of a circle using the relevant formulas.
- Appreciate the application of sector and segment area in real-life contexts such as circular gardens and fans.

In groups, learners are guided to:

- Use a compass to draw circles, cut out sectors of different angles and calculate their areas using A = θ/360 × πr².
- Draw a chord to form a segment and subtract the triangle area from the sector area to get the segment area.
- Solve problems involving circular gardens, fans and shaded regions involving sectors and segments.

How do we work out the area of different surfaces?

- Oxford Active Mathematics Grade 9 pg. 89
- Pair of compasses, ruler, protractor
- Sheets of paper

- Oral questions - Written assignments - Observation

Measurements

Area - Surface area of a cone

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

- Identify the faces of a cone and state the formula for its total surface area.
- Calculate the surface area of a cone using the formula SA = πr² + πrl.
- Appreciate the relevance of cone surface area in packaging, manufacturing and everyday objects.

In groups, learners are guided to:

- Open a paper cone to form a net, identify the circular base and curved surface.
- Measure the radius and slant height, calculate the area of each part and sum them.
- Collect cone-shaped objects from the environment and calculate their surface areas using the formula.

How do we work out the area of different surfaces?

- Oxford Active Mathematics Grade 9 pg. 93
- Paper cones, scissors, ruler, protractor

- Oral questions - Written assignments - Observation

Measurements

Area - Surface area of a sphere
Volume of Solids - Volume of a triangular-based prism

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

- State the formulas for the surface area of a sphere and a hemisphere.
- Calculate the surface area of a sphere and hemisphere using SA = 4πr² and SA = 3πr² respectively.
- Value the practical application of sphere surface area in manufacturing, painting and design.

In groups, learners are guided to:

- Collect balls of different sizes, measure their diameters, calculate radii and compute surface area using 4πr².
- Discuss real-life spherical objects such as globes, sports balls and storage tanks and estimate their surface areas.
- Discuss with family members the importance of calculating surface area in painting and manufacturing.

How do we work out the area of different surfaces?

- Oxford Active Mathematics Grade 9 pg. 95
- Spherical balls of different sizes
- Ruler and writing materials
- Oxford Active Mathematics Grade 9 pg. 98
- Triangular-based prism models

- Written tests - Oral questions - Observation

Measurements

Volume of Solids - Volume of a rectangular-based prism

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

- Identify the dimensions of a rectangular-based prism and explain the formula for its volume.
- Calculate the volume of rectangular-based prisms (cuboids) by multiplying base area by height.
- Value the application of prism volume in construction, storage and packaging planning.

In groups, learners are guided to:

- Collect and measure cuboid-shaped containers, calculate the base area and multiply by height.
- Verify volume calculations by counting unit cubes packed into a model.
- Solve problems involving the volume of tanks, boxes and rooms in real-life contexts.

How do we use the volume of solids in real-life situations?

- Oxford Active Mathematics Grade 9 pg. 100
- Rectangular-based prism models
- Ruler and writing materials

- Oral questions - Written assignments - Observation

Measurements

Volume of Solids - Volume of a pyramid

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

- State the formula for the volume of triangular, rectangular and square-based pyramids.
- Calculate the volume of various pyramids using V = ⅓ × base area × height.
- Appreciate the geometry of pyramids and their significance in architecture and cultural heritage.

In groups, learners are guided to:

- Collect or construct pyramid models, measure the base dimensions and perpendicular height.
- Apply the formula V = ⅓bh to calculate the volumes of pyramids of different shapes.
- Use relevant formulas to compare the volumes of a prism and a pyramid with the same base and height.

How do we determine the volume of different solids?

- Oxford Active Mathematics Grade 9 pg. 101
- Pyramid models (clay or cut paper)
- Ruler and writing materials

- Written assignments - Oral questions - Observation

Measurements

Volume of Solids - Volume of a cone

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

- State the formula for the volume of a cone and explain each variable.
- Calculate the volume of a cone using the formula V = ⅓πr²h.
- Appreciate the application of cone volume in everyday containers such as funnels, ice cream cones and silos.

In groups, learners are guided to:

- Collect cone-shaped objects such as funnels and party hats, measure the radius and height.
- Apply the formula V = ⅓πr²h to calculate the volume of the cone.
- Compare the volume of a cone with a cylinder of the same base and height and discuss the relationship.

How do we determine the volume of different solids?

- Oxford Active Mathematics Grade 9 pg. 103
- Cone-shaped models and containers
- Ruler and writing materials

- Oral questions - Written assignments - Observation

Measurements

Volume of Solids - Volume of a cone

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

- State the formula for the volume of a cone and explain each variable.
- Calculate the volume of a cone using the formula V = ⅓πr²h.
- Appreciate the application of cone volume in everyday containers such as funnels, ice cream cones and silos.

In groups, learners are guided to:

- Collect cone-shaped objects such as funnels and party hats, measure the radius and height.
- Apply the formula V = ⅓πr²h to calculate the volume of the cone.
- Compare the volume of a cone with a cylinder of the same base and height and discuss the relationship.

How do we determine the volume of different solids?

- Oxford Active Mathematics Grade 9 pg. 103
- Cone-shaped models and containers
- Ruler and writing materials

- Oral questions - Written assignments - Observation

Measurements

Volume of Solids - Volume of a frustum

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

- Describe a frustum and explain how it is derived by cutting a pyramid or cone.
- Calculate the volume of a frustum by subtracting the volume of the smaller solid from the larger one.
- Value the ability to calculate the volume of frustums in real-life containers such as buckets and flower pots.

In groups, learners are guided to:

- Cut a pyramid model into two parts to form a frustum and a smaller pyramid, calculate the volume of each.
- Use the formula: volume of frustum = volume of large pyramid − volume of small pyramid.
- Solve real-life problems involving the volume of frustum-shaped containers and objects.

How do we determine the volume of different solids?

- Oxford Active Mathematics Grade 9 pg. 105
- Pyramid models
- Ruler and writing materials

- Written tests - Oral questions - Observation

Measurements

Volume of Solids - Volume of a sphere

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

- State the formula for the volume of a sphere and explain each term.
- Calculate the volume of a sphere using the formula V = 4/3πr³.
- Appreciate the application of sphere volume in manufacturing spherical tanks, balls and globes.

In groups, learners are guided to:

- Collect balls of different sizes, measure the diameter, calculate the radius and compute volume using V = 4/3πr³.
- Discuss real-life spherical objects and estimate their volumes using the formula.
- Play games involving different-sized balls and work out their volumes using the formula.

How do we use the volume of solids in real-life situations?

- Oxford Active Mathematics Grade 9 pg. 107
- Spherical balls of different sizes
- Ruler and writing materials

- Oral questions - Written assignments - Observation

Measurements

Volume of Solids - Volume of a sphere

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

- State the formula for the volume of a sphere and explain each term.
- Calculate the volume of a sphere using the formula V = 4/3πr³.
- Appreciate the application of sphere volume in manufacturing spherical tanks, balls and globes.

In groups, learners are guided to:

- Collect balls of different sizes, measure the diameter, calculate the radius and compute volume using V = 4/3πr³.
- Discuss real-life spherical objects and estimate their volumes using the formula.
- Play games involving different-sized balls and work out their volumes using the formula.

How do we use the volume of solids in real-life situations?

- Oxford Active Mathematics Grade 9 pg. 107
- Spherical balls of different sizes
- Ruler and writing materials

- Oral questions - Written assignments - Observation

Measurements

Volume of Solids - Application of volume of solids in real life

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

- Identify real-life contexts where volumes of prisms, pyramids, cones, frustums and spheres are applied.
- Solve real-life problems involving volumes of different solids using appropriate formulas.
- Value the knowledge of volume in making practical decisions in construction and manufacturing.

In groups, learners are guided to:

- Solve multi-step problems involving volumes of containers, tanks and structures using relevant formulas.
- Discuss with family members how knowledge of volume is used in construction and packaging.
- Use IT tools to explore and calculate the volumes of different solid objects in engineering contexts.

How do we use the volume of solids in real-life situations?

- Oxford Active Mathematics Grade 9 pg. 108
- Writing materials
- Internet access

- Written tests - Oral questions - Observation

Measurements

Mass, Volume, Weight and Density - Conversion of units of mass

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

- State the units of mass and explain the relationships between kg, g, mg, Dg, hg and tonne.
- Convert units of mass from one form to another in different situations.
- Appreciate the importance of accurate mass measurement in trade and consumer protection.

In groups, learners are guided to:

- Study and identify different instruments used for measuring mass including balances and scales.
- Discuss the units of mass (kg, g, mg, hg, Dg, t) and their conversion factors using the ×10/÷10 rule.
- Solve problems involving conversion of mass units in real-life contexts such as weighing produce and luggage.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 110
- Beam balance or electronic balance
- Objects of different masses

- Oral questions - Written assignments - Observation

Measurements

Mass, Volume, Weight and Density - Conversion of units of mass: applications

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

- Identify practical situations where mass unit conversions are necessary.
- Solve problems requiring conversion of mass units in different real-life situations.
- Value the skill of mass conversion in ensuring accurate measurement and consumer protection.

In groups, learners are guided to:

- Collect and weigh different materials using a beam balance or electronic balance and record masses in different units.
- Convert between units by multiplying or dividing by the appropriate factor and verify answers.
- Solve real-life problems involving mass conversion such as weighing farm produce, ingredients and packages.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 111
- Beam balance and electronic balance
- Sand, stones and other materials

- Written assignments - Oral questions - Observation

Measurements

Mass, Volume, Weight and Density - Mass and weight

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

- Explain the difference between mass and weight and state the formula W = mg.
- Calculate weight from mass using the gravitational constant g = 10 N/kg.
- Value accurate measurement of mass and weight in ensuring consumer protection and health safety.

In groups, learners are guided to:

- Discuss the difference between mass and weight using different objects on a balance.
- Measure the mass of objects, then calculate weight using W = mg.
- Discuss contexts where both mass and weight are used such as weighing luggage, food and body health.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 113
- Beam balance or electronic balance
- Objects of different masses

- Oral questions - Written assignments - Observation

Measurements

Mass, Volume, Weight and Density - Mass and weight

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

- Explain the difference between mass and weight and state the formula W = mg.
- Calculate weight from mass using the gravitational constant g = 10 N/kg.
- Value accurate measurement of mass and weight in ensuring consumer protection and health safety.

In groups, learners are guided to:

- Discuss the difference between mass and weight using different objects on a balance.
- Measure the mass of objects, then calculate weight using W = mg.
- Discuss contexts where both mass and weight are used such as weighing luggage, food and body health.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 113
- Beam balance or electronic balance
- Objects of different masses

- Oral questions - Written assignments - Observation

Measurements

Mass, Volume, Weight and Density - Mass, volume and density

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

- Define density and state the formula ρ = m/V.
- Calculate density given the mass and volume of a substance.
- Appreciate the concept of density in explaining why some objects float and others sink.

In groups, learners are guided to:

- Collect cuboid-shaped blocks of different materials, measure their mass using a balance and dimensions using a ruler.
- Calculate the volume of each block and divide by mass to obtain density.
- Compare densities of different materials and discuss why denser objects sink in water.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 114
- Cuboid blocks of different substances
- Beam balance and ruler

- Oral questions - Written assignments - Observation

Measurements

Mass, Volume, Weight and Density - Mass, volume and density

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

- Define density and state the formula ρ = m/V.
- Calculate density given the mass and volume of a substance.
- Appreciate the concept of density in explaining why some objects float and others sink.

In groups, learners are guided to:

- Collect cuboid-shaped blocks of different materials, measure their mass using a balance and dimensions using a ruler.
- Calculate the volume of each block and divide by mass to obtain density.
- Compare densities of different materials and discuss why denser objects sink in water.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 114
- Cuboid blocks of different substances
- Beam balance and ruler

- Oral questions - Written assignments - Observation

Measurements

Mass, Volume, Weight and Density - Calculating mass, volume and density

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

- Describe the relationships among mass, volume and density using the formula ρ = m/V.
- Calculate mass, volume and density of different substances using the relevant formula.
- Value the use of density calculations in science, engineering and identifying materials.

In groups, learners are guided to:

- Fill containers of known volume with different substances (water, sand), measure the mass and calculate density.
- Rearrange the density formula to calculate mass (m = ρV) and volume (V = m/ρ) in different problems.
- Solve problems involving mass, volume and density in different real-life situations using IT devices or other resources.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 115
- Cylindrical containers, beam balance
- Sand, water and different substances

- Written assignments - Oral questions - Observation

Measurements

Mass, Volume, Weight and Density - Application of density

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

- Identify real-life situations where density is applied such as in materials science and fluid mechanics.
- Determine the density of different liquids and solids through practical investigation.
- Appreciate the role of density in differentiating substances and making informed materials choices.

In groups, learners are guided to:

- Fill a cylindrical container with water, measure mass and calculate density; repeat with salty water and cooking oil.
- Compare densities of different liquids and discuss floatation using the concept of relative density.
- Solve complex problems involving density, volume and mass of different solid and liquid substances.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 116
- Cylindrical containers, measuring cylinder
- Liquids (water, oil), solid objects

- Oral questions - Written tests - Observation

Measurements

Mass, Volume, Weight and Density - Application of density in real life

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

- Discuss real-life applications of density including floatation, construction and food science.
- Solve complex problems involving mass, volume, weight and density in different contexts.
- Value the knowledge of density and its applications in making informed daily decisions.

In groups, learners are guided to:

- Investigate whether different objects float or sink in water and relate the observations to their densities.
- Use IT tools to explore how density is measured and applied in industry and food science.
- Discuss with family members situations where density knowledge is applied in solving daily problems.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 117
- Water containers, objects of different densities
- Internet access

- Written tests - Oral questions - Observation

Measurements

Mass, Volume, Weight and Density - Application of density in real life

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

- Discuss real-life applications of density including floatation, construction and food science.
- Solve complex problems involving mass, volume, weight and density in different contexts.
- Value the knowledge of density and its applications in making informed daily decisions.

In groups, learners are guided to:

- Investigate whether different objects float or sink in water and relate the observations to their densities.
- Use IT tools to explore how density is measured and applied in industry and food science.
- Discuss with family members situations where density knowledge is applied in solving daily problems.

How do you weigh materials and objects?

- Oxford Active Mathematics Grade 9 pg. 117
- Water containers, objects of different densities
- Internet access

- Written tests - Oral questions - Observation

Measurements

Time, Distance and Speed - Speed in metres per second

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

- State the formula for speed and explain the relationship between distance, time and speed.
- Calculate speed in metres per second from given distance and time values.
- Appreciate the use of speed calculations in sports, transport and safety planning.

- Run or walk a 100 m race, record the time taken for each learner and calculate speed in m/s.
- Discuss the formula speed = distance ÷ time and solve problems using different units.
- Solve real-life problems involving athletes, vehicles and animals using speed in m/s.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 121
- Stopwatches or clocks
- Tape measure

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Speed in kilometres per hour

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

- Describe the relationship between speed in m/s and km/h and state the conversion factor.
- Calculate speed in km/h and convert between m/s and km/h accurately.
- Value the application of speed in km/h in road transport, journey planning and road safety.

In groups, learners are guided to:

- Use distance-time graphs to determine speed in km/h for different journeys.
- Calculate speed using distances between real Kenyan towns and actual journey times.
- Solve problems involving journeys between towns and discuss speed limits and road safety.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 122
- Graph paper and ruler
- Writing materials

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Average speed

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

- Explain the concept of average speed and how it differs from instantaneous speed.
- Calculate average speed for journeys with different speeds over different distances.
- Appreciate the relevance of average speed in planning multi-stage journeys and road safety.

In groups, learners are guided to:

- Analyse scenarios where a vehicle travels at different speeds on different legs of a journey.
- Work out average speed using total distance ÷ total time taken for the whole journey.
- Solve problems involving average speed in real-life transport scenarios such as bus, lorry and cyclist journeys.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 123
- Writing materials

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Average speed

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

- Explain the concept of average speed and how it differs from instantaneous speed.
- Calculate average speed for journeys with different speeds over different distances.
- Appreciate the relevance of average speed in planning multi-stage journeys and road safety.

In groups, learners are guided to:

- Analyse scenarios where a vehicle travels at different speeds on different legs of a journey.
- Work out average speed using total distance ÷ total time taken for the whole journey.
- Solve problems involving average speed in real-life transport scenarios such as bus, lorry and cyclist journeys.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 123
- Writing materials

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Average speed: applications

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

- Identify situations where average speed calculations are applied in real life.
- Solve multi-step problems involving average speed with stops and different legs of a journey.
- Develop a positive attitude towards using mathematical tools to plan and optimise travel.

In groups, learners are guided to:

- Calculate average speed for journeys with rest stops, different speeds on different sections and return trips.
- Analyse distance-time graphs to determine average speed for each segment of a journey.
- Solve problems involving journeys with multiple speed changes and stops at intermediate points.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 124
- Graph paper and writing materials

- Written tests - Oral questions - Observation

Measurements

Time, Distance and Speed - Velocity

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

- Explain the difference between speed and velocity and define displacement.
- Distinguish between speed and velocity and calculate velocity in given real-life situations.
- Appreciate the precision of velocity in describing motion in physics and engineering.

In groups, learners are guided to:

- Discuss the difference between distance and displacement using diagrams with directional arrows.
- Determine velocity of objects moving in specified directions and compare with speed values.
- Solve problems that distinguish between speed and velocity in real-life contexts.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 125
- Writing materials

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Velocity

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

- Explain the difference between speed and velocity and define displacement.
- Distinguish between speed and velocity and calculate velocity in given real-life situations.
- Appreciate the precision of velocity in describing motion in physics and engineering.

In groups, learners are guided to:

- Discuss the difference between distance and displacement using diagrams with directional arrows.
- Determine velocity of objects moving in specified directions and compare with speed values.
- Solve problems that distinguish between speed and velocity in real-life contexts.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 125
- Writing materials

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Acceleration

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

- Define acceleration and state the formula a = (v−u)/t.
- Calculate acceleration and deceleration using given initial velocity, final velocity and time values.
- Value the understanding of acceleration in road safety, sport science and engineering applications.

In groups, learners are guided to:

- Participate in short running events, record the starting and finishing velocities, calculate acceleration.
- Use stopwatch and tape measure to measure time and distance, then determine acceleration.
- Solve problems involving acceleration and deceleration using the formula a = (v−u)/t.

How do we observe speed in daily activities?

- Oxford Active Mathematics Grade 9 pg. 126
- Stopwatch and tape measure

- Written assignments - Oral questions - Observation

Measurements

Time, Distance and Speed - Longitudes on the globe

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

- Identify and describe longitudes on the globe including the Greenwich Meridian and their labelling.
- Distinguish between longitudes east and west of the Greenwich Meridian using a globe or map.
- Appreciate the global system of longitudes and their role in navigation and geography.

In groups, learners are guided to:

- Study a globe or maps and identify longitudes as imaginary lines running from north to south.
- Identify the Greenwich Meridian and distinguish east (0°–180°E) and west (0°–180°W) longitudes.
- Use a globe and maps to identify the longitudes of different cities in Kenya and across the world.

Why does time vary in different places of the world?

- Oxford Active Mathematics Grade 9 pg. 126
- Globe or map of the world

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Longitudes on the globe

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

- Identify and describe longitudes on the globe including the Greenwich Meridian and their labelling.
- Distinguish between longitudes east and west of the Greenwich Meridian using a globe or map.
- Appreciate the global system of longitudes and their role in navigation and geography.

In groups, learners are guided to:

- Study a globe or maps and identify longitudes as imaginary lines running from north to south.
- Identify the Greenwich Meridian and distinguish east (0°–180°E) and west (0°–180°W) longitudes.
- Use a globe and maps to identify the longitudes of different cities in Kenya and across the world.

Why does time vary in different places of the world?

- Oxford Active Mathematics Grade 9 pg. 126
- Globe or map of the world

- Oral questions - Written assignments - Observation

Measurements

Time, Distance and Speed - Longitudes and local time

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

- Explain how the earth's rotation relates to time differences across longitudes.
- Calculate the local time of a place given its longitude and the time at another location.
- Appreciate the global significance of time zones in international communication and travel.

In groups, learners are guided to:

- Discuss the relationship between longitudes and time using a globe and a light source.
- Calculate time differences between two places using longitude difference × 4 minutes per degree.
- Use IT devices to explore time zones in different parts of the world and solve real-life time problems.

Why does time vary in different places of the world?

- Oxford Active Mathematics Grade 9 pg. 127
- Globe, maps
- Digital resources and internet access

- Written tests - Oral questions - Observation

Measurements

Money - Currencies of other countries

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

- Identify currencies used in different countries and explain the concept of currency exchange.
- Distinguish between buying and selling rates of currency exchange.
- Appreciate the global nature of currency exchange in international trade and travel.

In groups, learners are guided to:

- Collect cut-outs of different currencies from old newspapers and magazines and match each to its country.
- Use digital devices to search for and list currencies of various countries.
- Visit a nearby bank or financial institution to find out the buying and selling rates of different currencies.

Why do we change currencies from one form to another?

- Oxford Active Mathematics Grade 9 pg. 132
- Old newspapers and magazines
- Digital devices and internet access

- Oral questions - Written assignments - Observation

Measurements

Money - Conversion of currencies

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

- Describe how currency conversion works using buying and selling rates from financial institutions.
- Calculate the amount received when converting currencies using given exchange rates.
- Value accurate currency conversion in protecting consumers during trade and travel.

In groups, learners are guided to:

- Use newspapers or visit financial institutions to find current exchange rates for different currencies.
- Fill in a currency exchange rate table and use it to convert between currencies.
- Solve worked examples converting Kenya shillings to foreign currencies and vice versa.

Why do we change currencies from one form to another?

- Oxford Active Mathematics Grade 9 pg. 133
- Newspapers with currency exchange rates
- Digital devices

- Oral questions - Written assignments - Observation

Measurements

Money - Conversion of currencies

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

- Describe how currency conversion works using buying and selling rates from financial institutions.
- Calculate the amount received when converting currencies using given exchange rates.
- Value accurate currency conversion in protecting consumers during trade and travel.

In groups, learners are guided to:

- Use newspapers or visit financial institutions to find current exchange rates for different currencies.
- Fill in a currency exchange rate table and use it to convert between currencies.
- Solve worked examples converting Kenya shillings to foreign currencies and vice versa.

Why do we change currencies from one form to another?

- Oxford Active Mathematics Grade 9 pg. 133
- Newspapers with currency exchange rates
- Digital devices

- Oral questions - Written assignments - Observation

Measurements

Money - Conversion of currencies: applications

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

- Identify situations where currency conversion is used in international trade and travel.
- Solve real-life problems involving conversion between different world currencies.
- Develop awareness of financial literacy and consumer protection in international transactions.

In groups, learners are guided to:

- Solve multi-step problems converting US dollars, Euros, Pounds, Yen and other currencies to and from Kenya shillings.
- Discuss the effect of exchange rate changes on the cost of imported goods.
- Use IT tools to find current exchange rates and apply them to solve real-life problems.

Why do we change currencies from one form to another?

- Oxford Active Mathematics Grade 9 pg. 134
- Writing materials
- Internet access

- Written tests - Oral questions - Observation

Measurements

Money - Import duty and excise duty

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

- Define import duty, excise duty and customs value and explain when each applies.
- Calculate import duty and excise duty charged on goods using given rates.
- Appreciate the role of import and excise duty in generating government revenue and protecting local industries.

In groups, learners are guided to:

- Visit the Kenya Revenue Authority (KRA) or invite a resource person to discuss import and excise duties.
- Work out import duty from given customs values and rates using the formula: duty = rate × customs value.
- Research goods exempted from import duty in Kenya and discuss the economic rationale.

How do we determine taxes charged on different goods?

- Oxford Active Mathematics Grade 9 pg. 136
- KRA resource materials
- Writing materials

- Written assignments - Oral questions - Observation

Measurements

Money - Import duty and excise duty

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

- Define import duty, excise duty and customs value and explain when each applies.
- Calculate import duty and excise duty charged on goods using given rates.
- Appreciate the role of import and excise duty in generating government revenue and protecting local industries.

In groups, learners are guided to:

- Visit the Kenya Revenue Authority (KRA) or invite a resource person to discuss import and excise duties.
- Work out import duty from given customs values and rates using the formula: duty = rate × customs value.
- Research goods exempted from import duty in Kenya and discuss the economic rationale.

How do we determine taxes charged on different goods?

- Oxford Active Mathematics Grade 9 pg. 136
- KRA resource materials
- Writing materials

- Written assignments - Oral questions - Observation

Measurements

Money - Value Added Tax

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

- Define Value Added Tax (VAT) and explain how it is calculated on goods and services.
- Calculate VAT using the formula VAT = rate × (customs value + import duty + excise duty).
- Value the role of VAT in public revenue generation and recognise it on shopping receipts.

In groups, learners are guided to:

- Collect shopping receipts and identify the VAT charged and the rate applied.
- Work out VAT on different items using the given formula and the 16% standard rate.
- Discuss imported and local goods that attract VAT and calculate the total cost of goods inclusive of VAT.

How do we determine taxes charged on different goods?

- Oxford Active Mathematics Grade 9 pg. 139
- Shopping receipts
- Writing materials

- Oral questions - Written assignments - Observation

Measurements

Money - Export duty and application of taxes in real life

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

- Define export duty and identify goods that attract export duty.
- Calculate export duty charged on exported goods using given rates.
- Appreciate the importance of paying taxes in supporting national development and public services.

In groups, learners are guided to:

- Discuss and research goods that attract export duty and those that are exempted in Kenya.
- Solve problems calculating export duty using the formula: duty = rate × value of export.
- Discuss with family members the different types of taxes and why paying taxes is important for national development.

How do we determine taxes charged on different goods?

- Oxford Active Mathematics Grade 9 pg. 140
- KRA resource materials
- Internet access

- Written tests - Oral questions - Observation

Measurements

Approximations and Errors - Approximation of quantities using arbitrary units

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

- Define an arbitrary unit and describe its use in approximating measurements of different quantities.
- Approximate lengths, areas, volumes, capacities and masses using arbitrary units.
- Appreciate the role of approximation in everyday measurement when standard tools are unavailable.

In groups, learners are guided to:

- Measure the classroom length in palm lengths, foot lengths and strides and compare results.
- Approximate the area of a surface using small and large squares and record findings.
- Approximate the volume of a box using small and large cubes and the capacity of containers using cups and jugs.

How do we estimate measurements of different quantities?

- Oxford Active Mathematics Grade 9 pg. 142
- Sticks, string, cups, jugs
- Small and large squares (cut paper)

- Oral questions - Written assignments - Observation

Measurements

Approximations and Errors - Errors in estimation of measurements

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

- Explain the concept of measurement error and how it arises from estimation.
- Calculate the error in a measurement by computing the difference between estimated and actual values.
- Develop a sense of responsibility in minimising errors when measuring quantities.

In groups, learners are guided to:

- Estimate the length of objects using palm lengths then measure with a ruler; record both values.
- Calculate the error = estimated measurement − actual measurement for each object.
- Discuss real-life situations where estimation errors have consequences such as in construction and medicine.

How do we estimate measurements of different quantities?

- Oxford Active Mathematics Grade 9 pg. 144
- Ruler, beam balance
- Objects of different sizes

- Written assignments - Oral questions - Observation

Measurements

Approximations and Errors - Errors in estimation of measurements

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

- Explain the concept of measurement error and how it arises from estimation.
- Calculate the error in a measurement by computing the difference between estimated and actual values.
- Develop a sense of responsibility in minimising errors when measuring quantities.

In groups, learners are guided to:

- Estimate the length of objects using palm lengths then measure with a ruler; record both values.
- Calculate the error = estimated measurement − actual measurement for each object.
- Discuss real-life situations where estimation errors have consequences such as in construction and medicine.

How do we estimate measurements of different quantities?

- Oxford Active Mathematics Grade 9 pg. 144
- Ruler, beam balance
- Objects of different sizes

- Written assignments - Oral questions - Observation

Measurements

Approximations and Errors - Percentage errors

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

- Describe percentage error and explain how it relates the error to the actual measurement.
- Calculate percentage error using the formula: percentage error = (error ÷ actual measurement) × 100%.
- Appreciate the use of percentage error in quality control and scientific measurement contexts.

In groups, learners are guided to:

- Estimate and measure different quantities (length, capacity, mass) and calculate the raw error for each.
- Apply the percentage error formula to each measurement and compare results across different quantities.
- Use IT devices to compute percentage errors and relate findings to consumer protection and quality assurance.

How do we estimate measurements of different quantities?

- Oxford Active Mathematics Grade 9 pg. 146
- Ruler, measuring cylinder, beam balance
- Internet access

- Written tests - Oral questions - Observation

Measurements

Approximations and Errors - Percentage errors

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

- Describe percentage error and explain how it relates the error to the actual measurement.
- Calculate percentage error using the formula: percentage error = (error ÷ actual measurement) × 100%.
- Appreciate the use of percentage error in quality control and scientific measurement contexts.

In groups, learners are guided to:

- Estimate and measure different quantities (length, capacity, mass) and calculate the raw error for each.
- Apply the percentage error formula to each measurement and compare results across different quantities.
- Use IT devices to compute percentage errors and relate findings to consumer protection and quality assurance.

How do we estimate measurements of different quantities?

- Oxford Active Mathematics Grade 9 pg. 146
- Ruler, measuring cylinder, beam balance
- Internet access

- Written tests - Oral questions - Observation

Measurements

Approximations and Errors - Application of approximations and errors in real life

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

- Identify real-life situations where approximations and errors are relevant such as in trade, science and engineering.
- Solve problems involving approximations and errors in various measurement contexts.
- Value accuracy and precision in measurement as a foundation for consumer protection and scientific inquiry.

In groups, learners are guided to:

- Solve real-life problems involving errors and percentage errors in capacity, mass and length measurements.
- Discuss how errors in measurement affect trade and consumer protection in everyday buying and selling.
- Discuss with family members how knowledge of approximations and errors is applied in their daily work and home activities.

How do we estimate measurements of different quantities?

- Oxford Active Mathematics Grade 9 pg. 148
- Writing materials
- Digital resources and internet access

- Written tests - Oral questions - Observation

Geometry

Coordinates and Graphs - Plotting points on a Cartesian plane
Coordinates and Graphs - Graphs of straight lines

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

- Identify the four quadrants, the x-axis and y-axis on a Cartesian plane.
- Plot given points accurately on a Cartesian plane and join them to form geometric shapes.
- Appreciate the use of coordinates in locating positions in real life such as on maps and globes.

In groups, learners are guided to:

- Work with peers to locate the point of intersection of x and y coordinates on a Cartesian plane.
- Draw a Cartesian plane and plot given points using (x, y) notation, placing points in all four quadrants.
- Join plotted points with straight lines to form triangles, quadrilaterals and other figures and name them.

How do we draw graphs of straight lines?

- Oxford Active Mathematics Grade 9 pg. 149
- Graph paper and ruler
- Oxford Active Mathematics Grade 9 pg. 151

- Oral questions - Written assignments - Observation

Geometry

Coordinates and Graphs - Parallel lines and their gradients

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

- Describe the relationship between the gradients of parallel lines on a Cartesian plane.
- Draw parallel lines and calculate their gradients to verify they are equal.
- Appreciate the application of parallel lines in design, architecture and road planning.

In groups, learners are guided to:

- Generate tables of values for pairs of parallel line equations and plot on the same Cartesian plane.
- Calculate the gradient of each parallel line and compare them.
- Solve problems involving equations of lines parallel to given lines through specific points.

How do we interpret graphs of straight lines?

- Oxford Active Mathematics Grade 9 pg. 154
- Graph paper and ruler

- Oral questions - Written assignments - Observation

Geometry

Coordinates and Graphs - Perpendicular lines and their gradients
Coordinates and Graphs - Applications of graphs of straight lines

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

- Explain the relationship between the gradients of perpendicular lines (product equals -1).
- Draw perpendicular lines on a Cartesian plane and verify the product of their gradients equals -1.
- Value the precision required when working with perpendicular lines in engineering and construction.

In groups, learners are guided to:

- Generate tables of values for pairs of perpendicular line equations and plot on the same Cartesian plane.
- Calculate the gradient of each perpendicular line, multiply them and discuss the result.
- Determine equations of lines perpendicular to given lines and passing through given points.

How do we interpret graphs of straight lines?

- Oxford Active Mathematics Grade 9 pg. 158
- Graph paper and ruler
- Oxford Active Mathematics Grade 9 pg. 162

- Written assignments - Oral questions - Observation

Data Handling and Probability

Data Interpretation (Grouped Data) - Class width

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

- Define the terms range and class width.
- Determine an appropriate class width for grouping a given set of data.
- Appreciate the value of grouping in organising large sets of data.

- Discuss the meaning of range and class width using a set of data
- Identify the highest and lowest values in a set of data and work out the range
- Work out an appropriate class width for grouping data into a given number of classes
- Collect data on the masses of learners in class and determine a suitable class width

How do we decide on a suitable class width when grouping data?

- Oxford Active Mathematics Learner's Book Grade 9 pg. 224
- Calculators
- Reference books
- Charts showing sets of data

- Oral questions - Written exercise - Observation

Data Handling and Probability

Data Interpretation (Grouped Data) - Frequency distribution tables of grouped data

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

- Describe a frequency distribution table for grouped data.
- Draw a frequency distribution table of grouped data using tallies.
- Appreciate the role of frequency tables in summarising data.

In groups, learners are guided to:
- Discuss how to organise data into classes of equal width
- Tally a set of data and record the frequency for each class
- Draw and complete a frequency distribution table for grouped data

How can grouped data be organised into a frequency distribution table?

- Oxford Active Mathematics Learner's Book Grade 9 pg. 227
- Calculators
- Manila paper and charts
- Reference books

- Written assignment - Observation - Oral questions

Data Handling and Probability

Data Interpretation (Grouped Data) - Modal class of grouped data
Data Interpretation (Grouped Data) - Mean of grouped data

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

- Define the modal class of grouped data.
- Identify the modal class from a frequency distribution table.
- Value the use of the modal class in interpreting data.

In groups, learners are guided to:
- Discuss the meaning of the modal class
- Draw a frequency distribution table for given data
- Identify the modal class from different frequency distribution tables

Which class in a set of grouped data occurs most frequently?

- Oxford Active Mathematics Learner's Book Grade 9 pg. 230
- Calculators
- Charts
- Reference books
- Oxford Active Mathematics Learner's Book Grade 9 pg. 233

- Oral questions - Written exercise - Observation

Data Handling and Probability

Data Interpretation (Grouped Data) - Median of grouped data

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

- Identify the median class of grouped data.
- Calculate the median of grouped data using the formula.
- Appreciate the median as a measure of central tendency.

In groups, learners are guided to:
- Use cumulative frequencies to determine the median class
- Identify the lower class boundary, class width and frequency of the median class
- Calculate the median from different sets of grouped data

How do we locate and calculate the median of grouped data?

- Oxford Active Mathematics Learner's Book Grade 9 pg. 236
- Calculators
- Charts
- Reference books

- Written assignment - Observation - Oral questions