MEASUREMENTS

Area of a Pentagon

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

-Identify and state the number of sides in a pentagon;
-Calculate the area of a regular pentagon;
-Apply the formula for finding the area of a pentagon in real-life situations;
-Develop genuine interest in calculating the area of regular pentagons.

In groups and individually, learners are guided to:
-Discuss the properties of regular polygons;
-Use cut-outs to work out the area of pentagons;
-Identify objects with pentagonal shapes in their environment;
-Calculate the area of a regular pentagon using the formula A = (5/2)s²sin(72°).

How do we determine the area of different surfaces?

-Mathematics learners book grade 9 page 87;
-Cut-outs of regular pentagons;
-Chart with diagrams of pentagons;
-Calculator;
-Ruler and protractor.

-Observation; -Oral questions; -Written exercises; -Group presentations.

MEASUREMENTS

Area of a Pentagon
Area of a Hexagon
Area of a Hexagon

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

-Work out the area of a regular pentagon when different measurements are given;
-Solve problems involving the height and side length of a pentagon;
-Interpret and solve word problems involving area of pentagons;
-Appreciate the use of geometry in calculating areas of pentagons.

In groups and individually, learners are guided to:
-Work out problems on area of pentagons with given side lengths;
-Calculate the area of pentagons where vertices are at a given distance from the center;
-Relate the height of triangles formed in a pentagon to the area;
-Solve practical problems involving area of pentagons.

How can we calculate the area of a pentagon in different situations?

-Mathematics learners book grade 9 page 89;
-Pentagonal objects;
-Calculator;
-Worked examples on the board.
-Mathematics learners book grade 9 page 90;
-Cut-outs of regular hexagons;
-Chart with diagrams of hexagons;
-Ruler and protractor;
-Calculator.
-Mathematics learners book grade 9 page 91;
-Hexagonal objects;

-Written exercises; -Homework assignments; -Group work assessment; -Mathematical problem-solving tasks.

MEASUREMENTS

Surface Area of Triangular and Rectangular-Based Prisms
Surface Area of Triangular, Rectangular and Square-Based Pyramids

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

-Draw a triangular prism and identify its faces, edges, and vertices;
-Develop a net for a triangular prism;
-Calculate the surface area of a triangular prism using its net;
-Appreciate the practical applications of surface area calculations.

In groups, learners are guided to:
-Collect from the environment objects that are triangular prisms;
-Draw and sketch nets of triangular prisms;
-Measure dimensions of the faces on the nets;
-Calculate the area of each face and add to find the total surface area;
-Discuss and share results with other groups.

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

-Mathematics learners book grade 9 page 94;
-Manila paper for making nets;
-Scissors;
-Rulers;
-Objects with triangular prism shapes;
-Glue.
-Mathematics learners book grade 9 page 95;
-Objects with rectangular prism shapes (boxes);
-Mathematics learners book grade 9 page 96;
-Objects with triangular pyramid shapes;

-Observation of practical work; -Oral questions; -Written exercises; -Group work assessment.

MEASUREMENTS

Surface Area of Triangular, Rectangular and Square-Based Pyramids
Area of a Sector and Segment of a Circle

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

-Draw a rectangular-based pyramid and identify its faces, edges, and vertices;
-Develop a net for a rectangular-based pyramid;
-Calculate the surface area of a rectangular-based pyramid;
-Appreciate the relationship between nets and surface area calculations.

In groups, learners are guided to:
-Draw and sketch nets of rectangular-based pyramids;
-Measure dimensions of the faces on the nets;
-Calculate the area of each face and add to find the total surface area;
-Discuss and share results with other groups;
-Solve problems involving surface area of rectangular-based pyramids.

How do we determine the surface area of a rectangular-based pyramid?

-Mathematics learners book grade 9 page 97;
-Manila paper for making nets;
-Scissors;
-Rulers;
-Objects with rectangular pyramid shapes;
-Glue.
-Mathematics learners book grade 9 page 99;
-Circular paper cut-outs;
-Protractors;
-Scientific calculators.

-Observation of practical work; -Oral questions; -Written exercises; -Model making assessment.

MEASUREMENTS

Area of a Sector and Segment of a Circle
Surface Area of a Cone in Real Life Situations
Surface Area of a Cone in Real Life Situations

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

-Define a segment of a circle;
-Differentiate between a sector and a segment of a circle;
-Calculate the area of a segment of a circle;
-Show genuine interest in calculating areas of segments.

In groups, learners are guided to:
-Draw circles and form segments by drawing chords;
-Cut out segments from paper circles;
-Derive the formula for the area of a segment (sector area minus triangle area);
-Calculate the area of segments with different angles and chord lengths;
-Discuss and share results with other groups.

How do we calculate the area of a segment of a circle?

-Mathematics learners book grade 9 page 101;
-Circular paper cut-outs;
-Protractors;
-Scissors;
-Rulers;
-Scientific calculators.
-Mathematics learners book grade 9 page 102;
-Conical objects (funnels, party hats);
-Glue.
-Mathematics learners book grade 9 page 103;
-Cone models;
-Scientific calculators;
-Charts showing formulas for surface area of cones.

-Observation of practical work; -Oral questions; -Written exercises; -Group work assessment.

MEASUREMENTS

Surface Area of a Sphere in Real Life Situations
Volume of Triangular and Rectangular-Based Prisms
Volume of Triangular and Rectangular-Based Prisms

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

-Identify and draw a sphere;
-Identify spherical objects in the environment;
-Calculate the surface area of a sphere using the formula A = 4πr²;
-Develop interest in calculating surface area of spheres.

In groups, learners are guided to:
-Collect objects with spherical shapes;
-Measure the diameter/radius of spherical objects;
-Calculate the surface area of spheres using the formula A = 4πr²;
-Discuss and share findings with other groups;
-Relate surface area of spheres to real-life applications.

What are some real-life objects that have a spherical shape?

-Mathematics learners book grade 9 page 104;
-Spherical objects (balls, oranges);
-Measuring tape/rulers;
-Scientific calculators;
-Charts showing formulas for surface area of spheres.
-Mathematics learners book grade 9 page 105;
-Triangular prism models;
-Rulers;
-Charts showing formulas for volume of triangular prisms.
-Mathematics learners book grade 9 page 107;
-Rectangular prism models (boxes);
-Charts showing formulas for volume of rectangular prisms.

-Observation; -Oral questions; -Written exercises; -Group presentations.

MEASUREMENTS

Volume of Triangular, Rectangular and Square-Based Pyramids
Volume of a Cone in Real Life Situations

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

-Identify triangular-based pyramids;
-Calculate the volume of a triangular-based pyramid using the formula V = ⅓ × area of base × height;
-Solve problems involving volume of triangular-based pyramids;
-Show interest in calculating volumes of pyramids.

In groups, learners are guided to:
-Identify and discuss models of triangular-based pyramids;
-Identify the base and height of triangular-based pyramids;
-Calculate the area of the triangular base;
-Calculate the volume using the formula V = ⅓ × area of base × height;
-Discuss and share results with other groups.

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

-Mathematics learners book grade 9 page 108;
-Triangular-based pyramid models;
-Rulers;
-Scientific calculators;
-Charts showing formulas for volume of pyramids.
-Mathematics learners book grade 9 page 109;
-Rectangular and square-based pyramid models;
-Mathematics learners book grade 9 page 110;
-Cone models;
-Charts showing formulas for volume of cones.

-Observation; -Oral questions; -Written exercises; -Problem-solving assessment.

MEASUREMENTS

Volume of a Sphere in Real Life Situations
Volume of a Frustum in Real Life Situations
Volume of a Frustum in Real Life Situations

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

-Identify spheres and their properties;
-Calculate the volume of a sphere using the formula V = ⅘ × πr³;
-Solve problems involving volume of spheres;
-Develop interest in calculating volumes of spheres.

In groups, learners are guided to:
-Identify and discuss models of spheres;
-Measure the radius of spherical objects;
-Calculate the volume using the formula V = ⅘ × πr³;
-Solve practical problems involving volume of spheres;
-Discuss and share results with other groups.

How do we determine the volume of a sphere?

-Mathematics learners book grade 9 page 112;
-Spherical objects (balls);
-Measuring tape/rulers;
-Scientific calculators;
-Charts showing formulas for volume of spheres.
-Mathematics learners book grade 9 page 113;
-Frustum models;
-Rulers;
-Charts showing formulas for volume of frustums.
-Mathematics learners book grade 9 page 114;

-Observation; -Oral questions; -Written exercises; -Problem-solving assessment.

MEASUREMENTS

Mass, Volume, Weight and Density - Instruments and Tools Used in Weighing
Mass, Volume, Weight and Density - Converting Units of Mass
Mass, Volume, Weight and Density - Relating Mass and Weight

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

-Identify different instruments and tools used in weighing;
-Describe the functions of various weighing instruments;
-Use weighing instruments correctly;
-Show interest in using weighing instruments.

In groups, learners are guided to:
-Identify and discuss different types of balances used for weighing;
-Identify commonly used balances in their locality;
-Discuss what different weighing instruments are used for;
-Practice using weighing instruments to measure mass of objects;
-Discuss and share findings with other groups.

How do you weigh materials and objects?

-Mathematics learners book grade 9 page 117;
-Different types of weighing instruments;
-Various objects to weigh;
-Charts showing different weighing instruments.
-Mathematics learners book grade 9 page 118;
-Weighing instruments;
-Charts showing relationship between different units of mass.
-Mathematics learners book grade 9 page 119;
-Spring balance;
-Digital devices for research.

-Observation; -Oral questions; -Practical assessment; -Group presentations.

MEASUREMENTS

Mass, Volume, Weight and Density - Determining Mass, Volume and Density
Mass, Volume, Weight and Density - Determining Density of Objects

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

-Define density;
-Understand the relationship between mass, volume, and density;
-Calculate density using the formula D = m/V;
-Show genuine interest in determining density of various substances.

In groups, learners are guided to:
-Measure the mass of different objects;
-Determine the volume of objects using water displacement method;
-Calculate the density of objects using the formula D = m/V;
-Complete a table with mass, volume, and density of different objects;
-Discuss and share findings with other groups.

How do we determine the density of an object?

-Mathematics learners book grade 9 page 121;
-Weighing instruments;
-Measuring cylinders;
-Various objects (coins, stones, metal pieces);
-Water;
-Scientific calculators.
-Mathematics learners book grade 9 page 122;
-Scientific calculators;
-Chart showing densities of common materials;
-Examples of applications of density in real life.

-Observation; -Oral questions; -Written exercises; -Practical assessment.

MEASUREMENTS

Mass, Volume, Weight and Density - Determining Mass Given Volume and Density
Mass, Volume, Weight and Density - Determining Volume Given Mass and 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:

-Rearrange the density formula to find mass;
-Calculate mass given volume and density using the formula m = D × V;
-Solve problems involving mass, volume, and density;
-Show interest in applying density concepts to find mass.

In groups, learners are guided to:
-Review the relationship between mass, volume, and density;
-Rearrange the formula D = m/V to find m = D × V;
-Calculate the mass of objects given their volume and density;
-Solve practical problems involving mass, volume, and density;
-Discuss and share results with other groups.

How can we determine the mass of an object if we know its volume and density?

-Mathematics learners book grade 9 page 123;
-Scientific calculators;
-Chart showing densities of common materials;
-Examples of applications of density in real life.
-Mathematics learners book grade 9 page 124;
-Stopwatch/timer;
-Measuring tape/rulers;
-Sports field or open area.

-Observation; -Oral questions; -Written exercises; -Problem-solving assessment.

MEASUREMENTS

Time, Distance and Speed - Working Out Speed in Km/h and m/s
Time, Distance and Speed - Working Out Average Speed in Real Life Situations
Time, Distance and Speed - Determining Velocity in Real Life Situations

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

-Calculate speed in kilometers per hour (km/h);
-Convert speed from m/s to km/h and vice versa;
-Solve problems involving speed in km/h;
-Appreciate the different units used for expressing speed.

In groups, learners are guided to:
-Record distance covered by vehicles in kilometers and time taken in hours;
-Calculate speed using the formula speed = distance/time;
-Express speed in kilometers per hour (km/h);
-Convert speed from m/s to km/h using the relationship 1 m/s = 3.6 km/h;
-Complete a table with distance, time, and speed;
-Discuss and share results with other groups.

Why do we need different units for measuring speed?

-Mathematics learners book grade 9 page 125;
-Scientific calculators;
-Chart showing conversion between m/s and km/h;
-Examples of speeds of various objects and vehicles.
-Mathematics learners book grade 9 page 126;
-Chart showing examples of average speed calculations;
-Examples of journey scenarios with varying speeds.
-Mathematics learners book grade 9 page 129;
-Stopwatch/timer;
-Measuring tape/rulers;
-Compass for directions.

-Observation; -Oral questions; -Written exercises; -Problem-solving assessment.

MEASUREMENTS

Time, Distance and Speed - Working Out Acceleration in Real Life Situations
Time, Distance and Speed - Identifying Longitudes on the Globe
Time, Distance and Speed - Relating Longitudes to Time on the Globe

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

-Define acceleration;
-Calculate acceleration using the formula a = (v-u)/t;
-Solve problems involving acceleration;
-Develop interest in understanding acceleration in real-life situations.

In groups, learners are guided to:
-Discuss the concept of acceleration;
-Record initial velocity, final velocity, and time taken for various movements;
-Calculate acceleration using the formula a = (v-u)/t;
-Understand deceleration as negative acceleration;
-Solve problems involving acceleration in real-life contexts;
-Discuss and share results with other groups.

How do we calculate acceleration?

-Mathematics learners book grade 9 page 130;
-Stopwatch/timer;
-Scientific calculators;
-Chart showing examples of acceleration calculations;
-Examples of acceleration in real-life situations.
-Mathematics learners book grade 9 page 131;
-Globe;
-World map showing longitudes;
-Digital devices for research;
-Charts showing the longitude system.
-Mathematics learners book grade 9 page 133;
-World map showing time zones;
-Charts showing the relationship between longitudes and time.

-Observation; -Oral questions; -Written exercises; -Problem-solving assessment.

MEASUREMENTS

Time, Distance and Speed - Determining Local Time of Places on Different Longitudes

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

-Calculate local time at different longitudes;
-Understand that time increases eastward and decreases westward;
-Solve problems involving local time at different longitudes;
-Show interest in understanding time zones.

In groups, learners are guided to:
-Review the relationship between longitudes and time;
-Calculate local time at different longitudes given the local time at a reference longitude;
-Understand that for every 15° change in longitude, time changes by 1 hour;
-Solve problems involving local time at different longitudes;
-Discuss and share results with other groups.

How do we calculate the local time at different longitudes?

-Mathematics learners book grade 9 page 134;
-Globe;
-World map showing time zones;
-Scientific calculators;
-Charts showing examples of local time calculations.
-Mathematics learners book grade 9 page 136;
-World map showing time zones and the International Date Line;
-Mathematics learners book grade 9 page 137;
-Digital devices showing current time in different cities;
-Scientific calculators.

-Observation; -Oral questions; -Written exercises; -Problem-solving assessment.

MEASUREMENTS

Money - Identifying Currencies Used in Different Countries
Money - Converting Currency from One to Another in Real Life Situations

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

-Identify currencies used in different countries;
-Match currencies with their respective countries;
-Recognize currency symbols;
-Show interest in learning about different currencies.

In groups, learners are guided to:
-Use digital devices to search and print pictures of currencies from: a) Neighboring countries b) Other African countries c) Common currencies used globally;
-Make a collage of different currencies on a piece of carton;
-Match currencies with their respective countries;
-Identify currency symbols (e.g., $, €, £, ¥);
-Display and present their collages to other groups.

Why do different countries use different currencies?

-Mathematics learners book grade 9 page 138;
-Digital devices for research;
-Pictures/samples of different currencies;
-Manila paper or carton;
-Charts showing currencies and their countries.
-Mathematics learners book grade 9 page 141;
-Exchange rate tables from newspapers or online sources;
-Scientific calculators;
-Digital devices for checking current exchange rates;
-Charts showing examples of currency conversions.

-Observation; -Oral questions; -Group presentations; -Assessment of currency collages.

MEASUREMENTS

Money - Converting Currency from One to Another in Real Life Situations
Money - Working Out Export Duties Charged on Goods
Money - Working Out Import Duties Charged on Goods

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

-Convert Kenyan currency to foreign currency;
-Use exchange rate tables to convert currencies;
-Solve problems involving currency conversion;
-Show interest in understanding international currency exchange.

In groups, learners are guided to:
-Review the concept of exchange rates;
-Understand that the selling rate is used when converting Kenyan Shillings to foreign currency;
-Convert Kenyan Shillings to various foreign currencies using the selling rate;
-Solve problems involving currency conversion;
-Discuss real-life situations where currency conversion is necessary;
-Discuss and share results with other groups.

How do exchange rates affect international trade?

-Mathematics learners book grade 9 page 142;
-Exchange rate tables from newspapers or online sources;
-Scientific calculators;
-Digital devices for checking current exchange rates;
-Charts showing examples of currency conversions.
-Mathematics learners book grade 9 page 143;
-Digital devices for research;
-Charts showing export duty rates;
-Examples of export scenarios.
-Charts showing import duty rates;
-Examples of import scenarios.

-Observation; -Oral questions; -Written exercises; -Problem-solving assessment.

MEASUREMENTS

Money - Working Out Excise Duty Charged on Goods
Money - Determining Value-Added Tax (VAT) Charged on Goods and Services
Approximations and Errors - Approximating Quantities in Measurements

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

-Define excise duty;
-Identify goods and services that attract excise duty;
-Calculate excise duty on goods and services;
-Show interest in understanding taxation systems.

In groups, learners are guided to:
-Use digital devices to search for the meaning of excise duty;
-Research goods that attract excise duty;
-Research percentage of excise duty on goods and services;
-Calculate excise duty on various goods and services;
-Solve problems involving excise duty;
-Discuss and share findings with other groups.

What is excise duty and how is it different from other taxes?

-Mathematics learners book grade 9 page 145;
-Digital devices for research;
-Scientific calculators;
-Charts showing excise duty rates;
-Examples of goods subject to excise duty.
-Supermarket receipts showing VAT;
-Charts showing VAT calculations.
-Mathematics learners book grade 9 page 148;
-Measuring tapes/rulers;
-Various objects to measure;
-Charts showing conventional and arbitrary units;
-Open space for measuring with strides.

-Observation; -Oral questions; -Written exercises; -Research presentation.

MEASUREMENTS
Geometry

Approximations and Errors - Determining Errors Using Estimations and Actual Measurements
Approximations and Errors - Determining Percentage Errors Using Actual Measurements
Coordinates and Graphs - Plotting points on a Cartesian plane

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

-Define error in measurements;
-Determine errors by comparing estimated and actual measurements;
-Calculate absolute errors in measurements;
-Develop genuine interest in understanding measurement errors.

In groups, learners are guided to:
-Estimate the measurements of various items in centimeters;
-Use a ruler to find the actual measurements of the items;
-Find the difference between the estimated and measured values;
-Understand that error = measured value - estimated value;
-Complete a table with estimated values, measured values, and errors;
-Discuss and share findings with other groups.

How do we determine errors in measurements?

-Mathematics learners book grade 9 page 149;
-Measuring tapes/rulers;
-Various objects to measure;
-Weighing scales/balances;
-Scientific calculators.
-Mathematics learners book grade 9 page 151;
-KLB Mathematics Grade 9 Textbook page 154
-Graph paper
-Ruler
-Pencils
-Charts with Cartesian plane
-Colored markers

-Observation; -Oral questions; -Written exercises; -Practical assessment.

Geometry

Coordinates and Graphs - Drawing a straight line graph
Coordinates and Graphs - Completing tables for linear equations
Coordinates and Graphs - Drawing parallel lines

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

Generate a table of values from the equation of a straight line;
Draw a straight line graph given an equation;
Appreciate the use of straight line graphs in representing linear relationships.

Learners generate a table of values for a given linear equation (e.g., y=-2x+5).
Learners plot the points on a Cartesian plane and join them to form a straight line.
Learners discuss and compare their results with other groups.

How do we generate a table of values from a linear equation?

-KLB Mathematics Grade 9 Textbook page 155
-Graph paper
-Ruler
-Pencils
-Calculator
-Blackboard illustration
-KLB Mathematics Grade 9 Textbook page 156
-Charts with prepared tables
-KLB Mathematics Grade 9 Textbook page 157
-Set square
-Charts showing parallel lines

-Oral questions -Group work -Written exercise -Assessment rubrics

Geometry

Coordinates and Graphs - Relating gradients of parallel lines
Coordinates and Graphs - Drawing perpendicular lines
Coordinates and Graphs - Relating gradients of perpendicular lines

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

Determine the gradients of straight lines;
Relate the gradients of parallel lines;
Value the importance of gradient in determining parallel lines.

Learners work in groups to generate tables of values for equations y=3x-4 and y=3x-1.
Learners draw the lines on the Cartesian plane and determine their gradients.
Learners compare the gradients and discuss the relationship between the gradients of parallel lines.

What is the relationship between the gradients of parallel lines?

-KLB Mathematics Grade 9 Textbook page 158
-Graph paper
-Ruler
-Calculator
-Manila paper
-Digital devices (optional)
-KLB Mathematics Grade 9 Textbook page 159
-Protractor
-Set square
-Charts showing perpendicular lines
-KLB Mathematics Grade 9 Textbook page 160
-Charts with examples of perpendicular lines

-Oral questions -Group discussion -Written exercise -Assessment rubrics

Geometry

Coordinates and Graphs - Applications of straight line graphs
Scale Drawing - Compass directions

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

Apply graphs of straight lines to real-life situations;
Interpret information from straight line graphs;
Value the use of graphs in representing real-life situations.

Learners work in groups to generate tables of values for parking charges in two different towns.
Learners draw graphs to represent the information on the same Cartesian plane.
Learners find the gradient of the two lines drawn and determine whether they are parallel.

How can straight line graphs help us solve real-life problems?

-KLB Mathematics Grade 9 Textbook page 165
-Graph paper
-Ruler
-Calculator
-Charts showing real-life applications
-Manila paper for presentations
-KLB Mathematics Grade 9 Textbook page 168
-Magnetic compass
-Plain paper
-Colored pencils
-Charts showing compass directions
-Maps

-Oral questions -Group discussion -Written exercise -Presentation

Geometry

Scale Drawing - Compass bearings
Scale Drawing - True bearings
Scale Drawing - Determining compass bearings

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

Identify compass bearings in different situations;
Measure and state positions using compass bearings;
Value the importance of compass bearings in navigation.

Learners trace diagrams showing compass bearings.
Learners measure angles from the south and north, and state the position of points using these angles.
Learners draw accurately various compass bearings like N70°E, S50°W, etc.

How do we express directions using compass bearings?

-KLB Mathematics Grade 9 Textbook page 170
-Protractor
-Ruler
-Plain paper
-Charts showing compass bearings
-Manila paper
-KLB Mathematics Grade 9 Textbook page 171
-Charts showing true bearings
-Diagrams for tracing
-KLB Mathematics Grade 9 Textbook page 173
-Charts with bearing examples
-Manila paper for group work

-Oral questions -Practical activity -Written exercise -Checklist

Geometry

Scale Drawing - Determining true bearings
Scale Drawing - Locating points using compass bearing and distance
Scale Drawing - Locating points using true bearing and distance

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

Determine true bearings in different situations;
Measure angles to find true bearings;
Value the use of true bearings in navigation.

Learners consider a diagram showing points C and D.
Learners identify and determine the bearing of D from C by measurement.
Learners measure the bearing of various points in different diagrams.

How do we determine the true bearing of one point from another?

-KLB Mathematics Grade 9 Textbook page 175
-Protractor
-Ruler
-Plain paper
-Worksheets with diagrams
-Charts with bearing examples
-KLB Mathematics Grade 9 Textbook page 178
-Drawing board
-Charts with examples
-Worksheets
-KLB Mathematics Grade 9 Textbook page 182
-Manila paper for presentations

-Oral questions -Practical activity -Written exercise -Checklist

Geometry

Scale Drawing - Angle of elevation
Scale Drawing - Determining angles of elevation
Scale Drawing - Angle of depression

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

Identify angles of elevation in real-life situations;
Make and use a clinometer to measure angles of elevation;
Appreciate the application of angles of elevation in real-life situations.

Learners perform an activity outside the classroom where they stand next to a flag pole and mark points at eye level and above.
Learners observe how the line of sight forms an angle when looking at higher objects.
Learners make a clinometer and use it to measure angles of elevation of objects in the school environment.

What is an angle of elevation and how do we measure it?

-KLB Mathematics Grade 9 Textbook page 186
-Protractor
-String
-Weight (about 25g)
-Cardboard
-Straight piece of wood
-Charts showing angles of elevation
-KLB Mathematics Grade 9 Textbook page 187
-Ruler
-Plain paper
-Drawing board
-Calculator
-Charts showing examples
-KLB Mathematics Grade 9 Textbook page 190
-Clinometer (made in previous lesson)
-Weight
-Charts showing angles of depression
-Diagrams

-Oral questions -Practical activity -Written exercise -Project assessment

Geometry

Scale Drawing - Determining angles of depression
Scale Drawing - Application in simple surveying
Scale Drawing - Survey using bearings and distances

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

Determine angles of depression in different situations;
Use scale drawings to find angles of depression;
Enjoy solving problems involving angles of depression.

Learners consider a stationary boat (B) that is 120 m away from the foot (F) of a cliff of height 80 m.
Learners make a scale drawing showing the positions of A, F, and B using a scale of 1 cm represents 20 m.
Learners measure the angle between the horizontal line passing through A and line AB to find the angle of depression.

How can we use scale drawings to determine angles of depression?

-KLB Mathematics Grade 9 Textbook page 192
-Protractor
-Ruler
-Plain paper
-Drawing board
-Calculator
-Charts with examples
-KLB Mathematics Grade 9 Textbook page 195
-Drawing paper
-Set square
-Pencil
-Field book (notebook)
-Charts with survey examples
-KLB Mathematics Grade 9 Textbook page 199
-Field book

-Oral questions -Scale drawing -Written exercise -Assessment rubrics

Geometry

Scale Drawing - Complex surveying problems
Scale Drawing - Project work on scale drawing
Similarity and Enlargement - Similar figures and properties

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

Solve complex surveying problems involving bearings and distances;
Create scale drawings of multiple points and features;
Show interest in scale drawing applications in real-life.

Learners study problems involving multiple points with bearings and distances between them.
Learners create scale drawings to determine unknown distances and bearings.
Learners discuss real-life applications of scale drawing in surveying and navigation.

How do we determine unknown distances and bearings using scale drawing?

-KLB Mathematics Grade 9 Textbook page 202
-Protractor
-Ruler
-Drawing paper
-Calculator
-Maps
-Charts with examples
-Measuring tape
-Compass
-Colored pencils
-Manila paper
-Drawing instruments
-KLB Mathematics Grade 9 Textbook page 203
-Cut-out shapes
-Charts showing similar figures

-Oral questions -Scale drawing -Written exercise -Assessment rubrics

Geometry

Similarity and Enlargement - Identifying similar objects
Similarity and Enlargement - Drawing similar figures

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

Identify similar objects in the environment;
Determine if given figures are similar;
Value the concept of similarity in everyday life.

Learners collect and classify objects according to similarity.
Learners identify pairs of similar figures from given diagrams.
Learners discuss real-life examples of similar objects and their properties.

How do we recognize similar objects in our environment?

-KLB Mathematics Grade 9 Textbook page 204
-Ruler
-Protractor
-Various geometric objects
-Charts with examples
-Worksheets with diagrams
-KLB Mathematics Grade 9 Textbook page 206
-Pair of compasses
-Drawing paper
-Calculator

-Oral questions -Group work -Written exercise -Observation

Geometry

Similarity and Enlargement - Properties of enlargement
Similarity and Enlargement - Negative scale factors
Similarity and Enlargement - Drawing images of objects

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

Determine properties of enlargement of different figures;
Locate the center of enlargement and find scale factors;
Value the application of enlargement in real-life situations.

Learners trace diagrams showing an object and its enlarged image.
Learners draw lines through corresponding points to find where they intersect (center of enlargement).
Learners find the ratios of corresponding lengths to determine the scale factor.

How do we determine the center and scale factor of an enlargement?

-KLB Mathematics Grade 9 Textbook page 209
-Ruler
-Tracing paper
-Colored pencils
-Grid paper
-Charts showing enlargements
-Diagrams for tracing
-KLB Mathematics Grade 9 Textbook page 211
-Charts showing negative scale factor enlargements
-KLB Mathematics Grade 9 Textbook page 214
-Charts showing steps of enlargement
-Manila paper

-Oral questions -Practical activity -Written exercise -Observation

Geometry

Similarity and Enlargement - Linear scale factor
Similarity and Enlargement - Using coordinates in enlargement
Similarity and Enlargement - Applications of similarity

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

Determine the linear scale factor of similar figures;
Calculate unknown dimensions using linear scale factors;
Value the application of linear scale factors in real-life problems.

Learners consider similar cones and find the ratios of their corresponding dimensions.
Learners study similar triangles and calculate the linear scale factor.
Learners use the scale factor to find unknown dimensions of similar figures.

How do we use linear scale factors to calculate unknown dimensions of similar figures?

-KLB Mathematics Grade 9 Textbook page 216
-Ruler
-Calculator
-Similar objects of different sizes
-Charts with examples
-Worksheets
-KLB Mathematics Grade 9 Textbook page 218
-Grid paper
-Colored pencils
-Charts with coordinate examples
-KLB Mathematics Grade 9 Textbook page 219
-Drawing paper
-Charts with real-life applications
-Manila paper for presentations

-Oral questions -Group work -Written exercise -Assessment rubrics

Geometry

Trigonometry - Angles and sides of right-angled triangles
Trigonometry - Sine ratio
Trigonometry - Cosine ratio

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

Identify angles and sides of right-angled triangles in different situations;
Distinguish between the hypotenuse, adjacent side, and opposite side;
Appreciate the relationship between angles and sides in right-angled triangles.

Learners draw right-angled triangles with acute angles and identify the longest side (hypotenuse).
Learners identify the side which together with the hypotenuse forms the angle θ (adjacent side).
Learners identify the side facing the angle θ (opposite side).

How do we identify different sides in a right-angled triangle?

-KLB Mathematics Grade 9 Textbook page 220
-Ruler
-Protractor
-Set square
-Drawing paper
-Charts with labeled triangles
-Colored markers
-KLB Mathematics Grade 9 Textbook page 222
-Calculator
-Charts showing sine ratio
-Manila paper
-KLB Mathematics Grade 9 Textbook page 223
-Charts showing cosine ratio
-Worksheets

-Oral questions -Observation -Written exercise -Checklist

Geometry

Trigonometry - Tangent ratio
Trigonometry - Reading tables of sines
Trigonometry - Reading tables of cosines and tangents

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

Identify tangent ratio from a right-angled triangle;
Calculate tangent of angles in right-angled triangles;
Appreciate the importance of tangent ratio in problem-solving.

Learners draw triangle ABC with specific angles and mark points on BC.
Learners draw perpendiculars from these points to AC and measure their lengths.
Learners calculate ratios of opposite side to adjacent side for different angles and discover the tangent ratio.

What is the tangent of an angle and how do we calculate it?

-KLB Mathematics Grade 9 Textbook page 225
-Ruler
-Protractor
-Calculator
-Drawing paper
-Charts showing tangent ratio
-Manila paper
-KLB Mathematics Grade 9 Textbook page 227
-Mathematical tables
-Worksheets
-Chart showing how to read tables
-Sample exercises
-KLB Mathematics Grade 9 Textbook page 229-231

-Oral questions -Practical activity -Written exercise -Checklist

Geometry

Trigonometry - Using calculators for trigonometric ratios
Trigonometry - Calculating lengths using trigonometric ratios

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

Determine trigonometric ratios of acute angles using calculators;
Compare values obtained from tables and calculators;
Value the use of calculators in finding trigonometric ratios.

Learners use calculators to find trigonometric ratios of specific angles.
Learners compare values obtained from calculators with those from mathematical tables.
Learners use calculators to find sine, cosine, and tangent of various angles.

How do we use calculators to find trigonometric ratios?

-KLB Mathematics Grade 9 Textbook page 233
-Scientific calculators
-Mathematical tables
-Worksheets
-Chart showing calculator keys
-Sample exercises
-KLB Mathematics Grade 9 Textbook page 234
-Ruler
-Drawing paper
-Charts with examples

-Oral questions -Practical activity -Written exercise -Checklist

Geometry

Trigonometry - Calculating angles using trigonometric ratios
Trigonometry - Application in heights and distances
Trigonometry - Application in navigation

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

Use trigonometric ratios to calculate angles in right-angled triangles;
Apply inverse trigonometric functions to find angles;
Enjoy solving problems involving trigonometric ratios.

Learners consider right-angled triangles with known sides.
Learners calculate trigonometric ratios using the known sides and use tables or calculators to find the corresponding angles.
Learners solve problems involving finding angles in right-angled triangles.

How do we find unknown angles in right-angled triangles using trigonometric ratios?

-KLB Mathematics Grade 9 Textbook page 235
-Scientific calculators
-Mathematical tables
-Ruler
-Drawing paper
-Charts with examples
-Worksheets
-KLB Mathematics Grade 9 Textbook page 237
-Charts with real-life examples
-Manila paper
-KLB Mathematics Grade 9 Textbook page 238
-Protractor
-Maps
-Charts with navigation examples

-Oral questions -Group work -Written exercise -Observation

Geometry
Data Handling and Probability
Data Handling and Probability

Trigonometry - Review and mixed applications
Data Interpretation - Appropriate class width
Data Interpretation - Finding range and creating groups

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

Apply trigonometric concepts in mixed application problems;
Solve problems involving both scale drawing and trigonometry;
Value the integration of different geometric concepts in problem-solving.

Learners solve a variety of problems that integrate different geometric concepts learned.
Learners apply scale drawing, bearings, similar figures, and trigonometric ratios to solve complex problems.
Learners discuss how different geometric concepts interconnect in solving real-world problems.

How can we integrate different geometric concepts to solve complex problems?

-KLB Mathematics Grade 9 Textbook page 240
-Scientific calculators
-Mathematical tables
-Ruler
-Protractor
-Drawing paper
-Past examination questions
-KLB Mathematics Grade 9 Textbook page 244
-Calculator
-Graph paper
-Manila paper
-Rulers
-Colored markers
-KLB Mathematics Grade 9 Textbook page 245
-Data sets
-Chart with examples

-Oral questions -Problem-solving -Written exercise -Assessment test

Data Handling and Probability

Data Interpretation - Frequency distribution tables
Data Interpretation - Creating frequency tables with different class intervals
Data Interpretation - Modal class

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

Draw frequency distribution tables of grouped data;
Use tally marks to organize data into frequency tables;
Value the importance of organizing data in tables.

Learners are presented with data on the number of tree seedlings that survived in 50 different schools.
Learners copy and complete a frequency distribution table using tally marks and frequencies.
Learners discuss and share their completed tables with other groups.

How do we organize data in a frequency distribution table?

-KLB Mathematics Grade 9 Textbook page 247
-Chart paper
-Ruler
-Calculator
-Manila paper
-Colored markers
-Graph paper
-Worksheets with data
-KLB Mathematics Grade 9 Textbook page 248
-Chart showing frequency distribution tables

-Oral questions -Group presentations -Written exercise -Checklist

Data Handling and Probability

Data Interpretation - Mean of ungrouped data
Data Interpretation - Mean of grouped data
Data Interpretation - Mean calculation in real-life situations

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

Calculate the mean of ungrouped data in a frequency table;
Multiply each value by its frequency and find their sum;
Show interest in calculating mean in real-life situations.

Learners consider the height, in metres, of 10 people recorded in a frequency distribution table.
Learners complete a table showing the product of height and frequency (fx).
Learners find the sum of frequencies, sum of fx, and divide to find the mean.

How do we calculate the mean of data presented in a frequency table?

-KLB Mathematics Grade 9 Textbook page 249
-Calculator
-Chart showing frequency tables
-Worksheets
-Manila paper
-Colored markers
-KLB Mathematics Grade 9 Textbook page 250
-Graph paper
-Chart with examples
-KLB Mathematics Grade 9 Textbook page 251

-Oral questions -Written exercise -Observation -Assessment rubrics

Data Handling and Probability

Data Interpretation - Median of grouped data
Data Interpretation - Calculating median using formula
Data Interpretation - Median calculations in real-life situations

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

Determine the median of grouped data;
Find cumulative frequencies to locate the median class;
Value the importance of median in data interpretation.

Learners consider the mass of 50 learners recorded in a table.
Learners complete the column for cumulative frequency.
Learners find the sum of frequency, divide by 2, and identify the position of the median mass.

How do we determine the median of grouped data?

-KLB Mathematics Grade 9 Textbook page 252
-Calculator
-Chart showing cumulative frequency tables
-Worksheets
-Manila paper
-Colored markers
-KLB Mathematics Grade 9 Textbook page 253
-Graph paper
-Chart showing median formula
-KLB Mathematics Grade 9 Textbook page 254
-Chart with example calculations
-Worksheets with real-life data

-Oral questions -Written exercise -Group presentations -Observation

Data Handling and Probability

Probability - Equally likely outcomes
Probability - Range of probability

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

Perform experiments involving equally likely outcomes;
Record outcomes of chance experiments;
Appreciate that some events have equal chances of occurring.

Learners work in groups to flip a fair coin 20 times.
Learners record the number of times heads and tails come up.
Learners divide the number of times heads or tails comes up by the total number of tosses to find probabilities.

What makes events equally likely to occur?

-KLB Mathematics Grade 9 Textbook page 256
-Coins
-Chart paper
-Table for recording outcomes
-Manila paper
-Colored markers
-KLB Mathematics Grade 9 Textbook page 257
-Dice
-Chart showing probability scale (0-1)

-Oral questions -Practical activity -Group work assessment -Observation

Data Handling and Probability

Probability - Complementary events
Probability - Mutually exclusive events
Probability - Experiments with mutually exclusive events

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

Calculate probability of complementary events;
Understand that sum of probabilities of complementary events is 1;
Show interest in applying complementary probability in real-life situations.

Learners discuss examples of complementary events.
Learners solve problems where the probability of one event is given and they need to find the probability of its complement.
Learners verify that the sum of probabilities of an event and its complement equals 1.

How are complementary events related in terms of their probabilities?

-KLB Mathematics Grade 9 Textbook page 258
-Calculator
-Chart showing complementary events
-Worksheets with problems
-Manila paper
-Colored markers
-Coins
-Chart with examples of mutually exclusive events
-Flashcards with different scenarios
-KLB Mathematics Grade 9 Textbook page 259
-Dice
-Colored objects in boxes
-Chart showing probability calculations

-Oral questions -Written exercise -Group work assessment -Observation

Data Handling and Probability

Probability - Independent events
Probability - Calculating probabilities of independent events
Probability - Tree diagrams for single outcomes

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

Perform experiments involving independent events;
Understand that outcome of one event doesn't affect another;
Show interest in applying independent events probability in real-life.

Learners toss a fair coin and a fair die at the same time and record outcomes.
Learners repeat the experiment several times.
Learners discuss that the outcome of the coin toss doesn't affect the outcome of the die roll (independence).

What makes events independent from each other?

-KLB Mathematics Grade 9 Textbook page 260
-Coins and dice
-Table for recording outcomes
-Chart showing examples of independent events
-Manila paper
-Colored markers
-KLB Mathematics Grade 9 Textbook page 261
-Calculator
-Chart showing multiplication rule
-Worksheets with problems
-KLB Mathematics Grade 9 Textbook page 262
-Chart paper
-Ruler
-Worksheets with blank tree diagrams
-Chart showing completed tree diagrams

-Oral questions -Practical activity -Group discussions -Observation

Data Handling and Probability

Probability - Complex tree diagrams

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

Draw more complex probability tree diagrams;
Use tree diagrams to solve probability problems;
Appreciate the value of tree diagrams in visualizing probability.

Learners draw tree diagrams for various probability scenarios like balls of different colors in a bag.
Learners use tree diagrams to find probabilities of different outcomes.
Learners interpret tree diagrams to solve probability problems.

How do we use tree diagrams to solve more complex probability problems?

-KLB Mathematics Grade 9 Textbook page 263
-Chart paper
-Ruler
-Calculator
-Chart showing complex tree diagrams
-Worksheets with problems
-Colored markers

-Oral questions -Written exercise -Group presentations -Assessment rubrics