Statistical Methods

Introduction and Compound Bar Graphs

By the end of the lesson, the learner should be able to:
Analyse and interpret statistical data
Present statistical data using appropriate methods
Highlight steps followed when constructing compound/cumulative bar graphs
Find totals and cumulative totals for data

Q/A to review basic statistical concepts and simple bar graphs; Exposition of steps followed when constructing compound bar graphs; Guided activity using Table 1.1 crop production data; Practice finding cumulative totals and suitable scales

Graph paper, Rulers, Calculators, Table 1.1 crop production data

Secondary Geography Form 3 Student's Book, Pages 1-3

Statistical Methods

Compound Bar Graphs - Analysis and Construction Practice
Compound Bar Graphs - Interpretation and Advantages/Disadvantages

By the end of the lesson, the learner should be able to:
Find suitable scale by considering largest and smallest values
Draw outline of each bar with components
Derive comprehensive key and label axes
Insert short and clear title

Exposition of scale selection and construction techniques; Drawing of compound bar graphs with proper shading; Detailed discussion on labeling and titling; Analysis of Fig. 1.1; Practice construction using Table 1.2 Kenya's export crops data

Colored pencils for shading, Construction materials, Table 1.2 data
Previously constructed graphs, Analysis worksheets

Secondary Geography Form 3 Student's Book, Pages 2-4

Statistical Methods

Proportional Circles - Construction Methods
Proportional Circles - Area Method and Analysis

By the end of the lesson, the learner should be able to:
Construct proportional circles using diameter method
Round off totals to nearest thousand
Select suitable scale for diameters
Use radii figures to draw different circles

Students determine value of angles for variables; Exposition of proportional circles concept; Demonstration using Table 1.3 sugar production data; Guided calculation of radii using suitable scales; Drawing of circles using calculated radii

Calculators, Compasses, Table 1.3 sugar production data, Plain paper
Square root tables, Construction materials, Table 1.6 data

Secondary Geography Form 3 Student's Book, Pages 3-5

Statistical Methods

Simple Pie Charts - Construction
Proportional Divided Circles - Construction
Pie Charts - Analysis and Interpretation

By the end of the lesson, the learner should be able to:
Systematically convert each component as percentage of whole
Convert percentage into degrees (360° = 100%)
Draw circle of convenient size using compass
Measure and draw calculated angles using protractor

Students determine value of angles for the variables; Exposition of conversion from raw data to percentages to degrees; Guided practical activity using land use example; Practice measuring angles starting with largest segment clockwise; Brief discussion on proper labeling and shading

Protractors, Compasses, Land use data example, Colored pencils
Table 1.9 mortality data, Square root tables, Construction materials
Constructed pie charts, Fig. 1.4 and Fig. 1.5 references, Analysis guidelines

Secondary Geography Form 3 Student's Book, Pages 5-7

Statistical Methods

Advantages and Disadvantages of All Methods

By the end of the lesson, the learner should be able to:
State advantages of each statistical method
Identify disadvantages and limitations
Compare different methods of data presentation
Evaluate when to use each method appropriately

Brain storming on advantages of each method; Detailed discussion of disadvantages: tedious calculations, time-consuming construction, difficulty with small values; Comparison of visual impressions and data types; Q/A on appropriate method selection

Comparison charts, Various sample statistical presentations, Method evaluation criteria

Secondary Geography Form 3 Student's Book, Pages 2-10

External Land Forming Processes

Introduction and Definition of Weathering
Agents of Weathering

By the end of the lesson, the learner should be able to:
Define weathering as process of rock breakdown in situ
Explain denudation as collective term for external processes
Distinguish between weathering and other external processes
Identify weathering agents: heat, water, dissolved substances, plants and animals

Q/A session reviewing internal land forming processes from Form Two; Exposition of denudation concept and external processes; Definition of weathering and regolith formation; Discussion of weathering agents and their effects on rocks

Charts showing external vs internal processes, Rock samples showing weathering effects, Diagrams of weathering agents
Rock samples, Temperature demonstration materials, Water pH testing materials, Examples of plant root damage to rocks

Secondary Geography Form 3 Student's Book, Pages 41-42

External Land Forming Processes

Factors Influencing Weathering

By the end of the lesson, the learner should be able to:
Explain how climate elements influence weathering rates
Analyze role of plants and animals in weathering processes
Describe how relief affects weathering on different slopes
Examine chemical composition effects: color differences and mineral composition

Brain storming on weathering factors; Discussion of climatic elements: sunshine, rain, frost, temperatures; Analysis of plant and animal contributions; Study of relief influence on weathering rates; Examination of rock color absorption and mineral composition effects

Climate charts, Relief diagrams, Rock samples of different colors and compositions, Examples from highland and lowland areas

Secondary Geography Form 3 Student's Book, Pages 44-45

External Land Forming Processes

Rock Structure, Texture and Physical Weathering Introduction

By the end of the lesson, the learner should be able to:
Explain rock structure as mode of jointing and planes of weakness
Describe texture as crystal size and its weathering effects
Define mechanical weathering as disintegration without chemical changes
Identify areas where physical weathering is common

Exposition of rock structure using Figures 3.1(a), (b) showing spheroidal weathering; Discussion of jointing patterns and resulting weathering types; Analysis of crystal size effects on weathering rates; Introduction to mechanical weathering in vegetation-free areas

Figures 3.1(a), (b), Rock samples showing different crystal sizes, Examples from Bunyore, Seme Hills, Sang'alo areas

Secondary Geography Form 3 Student's Book, Pages 45-47

External Land Forming Processes

Physical Weathering Processes - Block Disintegration and Exfoliation

By the end of the lesson, the learner should be able to:
Describe block disintegration through temperature changes and diurnal ranges
Explain exfoliation as peeling off of rock surfaces
Identify formation of exfoliation domes
Analyze conditions leading to these weathering processes

Detailed discussion of block disintegration using Figure 3.3; Analysis of desert temperature conditions and rock expansion/contraction; Study of exfoliation process using Figure 3.4; Examination of exfoliation dome formation using Figure 3.5

Figure 3.3 rock blocks, Figures 3.4 and 3.5 exfoliation examples, Temperature demonstration materials, Examples from desert regions

Secondary Geography Form 3 Student's Book, Pages 47-48

External Land Forming Processes

Physical Weathering - Granular Disintegration, Frost Action and Crystal Growth

By the end of the lesson, the learner should be able to:
Explain granular disintegration in heterogeneous rocks
Describe freezing and thawing effects in tundra and mountain regions
Identify frost action results: congelifraction, scree, talus
Analyze crystal growth in dry climates leading to alveoli and taffoni formation

Exposition of granular disintegration using Figure 3.6; Detailed discussion of frost action using Figure 3.7; Analysis of congelifraction and angular fragment formation; Study of crystal growth and crystallisation processes; Examples from Mounts Kenya, Kilimanjaro, Rwenzori and Ol Njorowa Gorge

Figure 3.6 granular disintegration, Figure 3.7 frost action, Figure 3.8 Ol Njorowa Gorge, Examples from East African mountains

Secondary Geography Form 3 Student's Book, Pages 48-50

External Land Forming Processes

Physical Weathering - Slaking and Pressure Release
Chemical Weathering Processes - Solution and Hydrolysis

By the end of the lesson, the learner should be able to:
Describe slaking as water uptake and loss in clay-containing rocks
Explain pressure release or unloading in exposed rocks
Identify areas experiencing these weathering processes
Analyze sheeting effects in granitic rocks

Discussion of slaking process in clay rocks during wet and dry seasons; Analysis of coastal Jurassic rocks examples: Miritini, Tudor, Port Reitz; Explanation of pressure release as denudation removes overlying rocks; Study of sheeting in granitic areas: Nyika plateau, Machakos, Maragoli, Bunyore

Examples from coastal Kenya, Granitic rock samples, Areas experiencing pressure release, Activity 3.4 practical demonstration
Chemical equation charts, Examples of salt pans, Rock samples containing feldspar, Areas showing hydrolysis: Wundanyi, Bunyore

Secondary Geography Form 3 Student's Book, Pages 50-51

External Land Forming Processes

Chemical Weathering - Oxidation, Carbonation and Hydration

By the end of the lesson, the learner should be able to:
Explain oxidation process in iron-containing rocks
Describe carbonation affecting calcium carbonate rocks
Analyze hydration as water absorption causing rock expansion
Identify areas and examples of these weathering processes

Study of oxidation chemical equation and ferric oxide formation; Analysis of carbonation process using chemical equation; Discussion of limestone dissolution and calcium bicarbonate formation; Explanation of hydration process and spheroidal weathering; Examples from coastal limestone areas: Kambe, Bamburi, Kilifi

Chemical equation demonstrations, Rock samples showing oxidation effects, Limestone samples, Examples of spheroidal weathering in basalt

Secondary Geography Form 3 Student's Book, Pages 53-56

External Land Forming Processes

Chemical Weathering Results and Biological Weathering

By the end of the lesson, the learner should be able to:
Identify formation of tors through deep weathering processes
Explain biological weathering through plant action
Describe animal contributions to weathering
Analyze human activities causing weathering

Analysis of tor formation using Figure 3.9; Study of examples: Bunyore, Maragoli, Amukura, Taita Hills, Lukenya, Mavoloni; Detailed discussion of tree root action using Figure 3.10; Examination of plant chemical contributions: algae, mosses, lichen; Analysis of animal effects: cattle pressure, burrowing, chemical excretions

Figure 3.9 tors examples, Figure 3.10 tree root action, Examples of biological weathering in local environment, Human activity examples

Secondary Geography Form 3 Student's Book, Pages 56-58

External Land Forming Processes

Biological Weathering - Human Activities and Significance of Weathering

By the end of the lesson, the learner should be able to:
Identify human activities causing weathering: deforestation, blasting, industrialisation
Explain acid rain effects from industrial emissions
Analyze burning and irrigation contributions to weathering
Discuss significance of weathering in soil formation, construction, tourism and economics

Study of human weathering activities using Figure 3.11 quarrying; Discussion of industrialisation effects: Carbon IV Oxide, sulphur dioxide emissions; Analysis of acid rain formation and corrosive effects; Examples from Copper Belt Zambia, Webuye Kenya; Study of agricultural burning and irrigation effects

Figure 3.11 quarrying, Examples of industrial weathering, Acid rain demonstration materials, Local examples of human-induced weathering

Secondary Geography Form 3 Student's Book, Pages 58-60

External Land Forming Processes

Significance of Weathering and Economic Importance

By the end of the lesson, the learner should be able to:
Explain weathering importance in soil formation processes
Describe weathering role in quarrying and construction industries
Identify weathering creating tourist attractions
Analyze economic products from weathering: bauxite, kaolite, clay

Exposition of weathering as initial stage in soil formation; Discussion of quarrying importance for building and construction; Analysis of tourist attractions: Kit Mikayi, Crying Stone using Figure 3.12; Study of economic products: bauxite from hydrolysis, kaolite from granite rotting, clay for pottery and bricks

Figure 3.12 Crying Stone of Kakamega, Examples of weathering tourist sites, Economic product samples, Engineering consideration examples

Secondary Geography Form 3 Student's Book, Pages 60-61

Mass Wasting

Introduction, Definition and Factors Influencing Mass Wasting
Slow Mass Wasting Processes

By the end of the lesson, the learner should be able to:
Define mass wasting as downward movement of weathered material under gravity
Distinguish between mass wasting and mass movement
Explain factors influencing mass wasting: slope, material nature, climate, vegetation
Analyze crustal forces and human activities effects

Q/A session reviewing weathering from previous chapter; Exposition of mass wasting concept and gravity influence; Discussion of water's role in overcoming resistance; Brain storming on factors affecting movement: slope angle, rock types, climate effects, vegetation role, human activities

Charts showing gravity effects, Slope demonstrations, Rock samples, Climate charts, Examples of human activities
Figures 4.1, 4.2, 4.3, Examples from mountains, Soil movement demonstrations, Cold climate examples

Secondary Geography Form 3 Student's Book, Pages 53-54

Mass Wasting

Rapid Mass Wasting - Earthflows, Mudflows and Avalanches

By the end of the lesson, the learner should be able to:
Describe earthflows in humid areas with shallow scars and terminal points
Explain mudflows as super-saturated material with high water content
Define avalanches as gravitational fall of ice and rock material
Analyze factors influencing rapid movements and compare characteristics

Study of earthflows using Figure 4.4; Analysis of mudflow formation, factors and examples from North Eastern Kenya; Discussion of avalanche characteristics in temperate regions; Comparison of movement speeds, water content and locations; Examples from volcanic slopes and arctic regions

Figure 4.4 earthflows, Mudflow examples, Avalanche examples from temperate regions, Factor comparison charts

Secondary Geography Form 3 Student's Book, Pages 56-57

Mass Wasting

Landslides - Types and Characteristics
Effects of Mass Wasting on Physical and Human Environment

By the end of the lesson, the learner should be able to:
Explain landslides as sudden movement with small water content
Describe slump as intermittent movement with backward rotation
Distinguish debris slide, debris fall, rock fall and rock slide characteristics
Analyze examples from Kenya and East Africa: Fort Portal, Limuru-Longonot, road cuttings

Introduction to landslide causes and triggering factors; Study of slump development using Figures 4.5 and 4.6; Analysis of debris movements and rock movements; Examination of Kenyan examples: Kabarnet-Iten, Mwatate-Wundanyi, Kaseve roads; Discussion of infrastructure impacts and geological plane movements

Figures 4.5, 4.6 slump examples, Road cutting examples, Rock samples, Examples from Uganda and Kenya
Figures 4.9, 4.10, Soil fertility examples, Disaster case studies, Environmental conservation examples

Secondary Geography Form 3 Student's Book, Pages 57-60