Infographics and Introduction to measures of central tendency for SS 1

Class: SS 1
Term: First Term
Week: 8
Age: 15 years
Duration: 60 minutes
Subject: Economics
Curriculum Theme: Basic Principles of Economics
Focal competence: Collecting and organizing data; using economic tools to interpret and analyze data for decision making
Key competencies/values: ICT and Digital Competencies; Digital Competencies
Skills:

• Computing the measures of central tendency

Previous Lesson: Basic Economic Tools, Data Collection, Frequency Distribution, Tables and Charts
Topic: Basic Economic Tools: Infographics
Subject Matter: Infographics, Introduction to measures of central tendency

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• Explain what infographics are.
• Identify the types of measures of central tendency.
• State the formulas for calculating the mean.

Affective Domain

• Appreciate the importance of infographics in presenting economic data.
• Recognize the relevance of central tendency measures in economic analysis.

Psychomotor Domain

• Demonstrate how to convert raw data into infographics.
• Compute the mean, median, and mode for a given set of data.
• Create a simple infographic using raw economic data.

Social Domain

• Collaborate effectively in groups to collect and analyze economic data.

Reference Materials

The following resources were used in planning this lesson:

• 2025 New Revised Senior Secondary Education Curriculum (SSEC)
• Relevant State Unified Scheme of Work
• A suitable Economics textbook for Senior Secondary 1
• The HeadTeacher Scheme of work For The New Revised Senior Secondary Education Curriculum (SSEC)

Instructional Materials

The teacher will teach this lesson with the aid of:

• Data sets (e.g., family sizes, market prices, production figures)
• Electronic devices (smartphones, tablets, laptops)
• Internet access
• Graph sheets
• Rulers
• Whiteboard/Blackboard
• Markers/Chalk

Rationale for the Lesson

This lesson is essential for students to understand how economic data can be effectively visualized and summarized. It equips them with practical skills in data presentation through infographics and basic statistical analysis using measures of central tendency. These skills are fundamental for interpreting economic trends, making informed decisions, and preparing for further studies in economics.

Prerequisite/Previous Knowledge

Students should have a basic understanding of what data is and simple methods of data collection from previous lessons.

Lesson Content/Board Summary

Basic Economic Tools: Infographics and Introduction to Measures of Central Tendency

Infographics

Infographics are visual representations of information, data, or knowledge intended to present complex information quickly and clearly. They combine text, images, and data visualizations (like charts and graphs) to tell a story or explain a concept in an engaging way.

Elements of an Infographic

Effective infographics typically include:

1. Compelling Headline: A clear and concise title that grabs attention.
2. Visuals: Icons, images, illustrations, charts, and graphs that represent data.
3. Content/Text: Key facts, statistics, and explanations that support the visuals.
4. Data: Numerical information presented in an organized and understandable manner.
5. Source: A reference to where the data or information was obtained.

Importance of Infographics in Economics

Infographics are valuable in economics because they:

1. Simplify complex economic data and concepts, making them easier to understand for a wider audience.
2. Highlight key trends, patterns, and relationships in economic data quickly.
3. Aid in decision-making by presenting summary insights from economic scenarios (e.g., market trends, production outputs, consumer behavior).
4. Make economic reports and presentations more engaging and memorable.
5. Facilitate comparison of economic indicators across different regions or time periods.

Steps to Create a Simple Infographic

Creating an infographic involves several steps:

1. Choose a Topic and Collect Data: Select an economic topic (e.g., household income, unemployment rates, market prices) and gather relevant raw data.
2. Outline Your Story: Decide the main message or story you want to convey with your data.
3. Select Visuals: Choose appropriate charts, graphs, icons, and images to represent your data and concepts.
4. Design and Arrange: Use design tools (like Canva, Google Slides, or even graph sheets) to arrange your elements logically and aesthetically.
5. Add Text and Sources: Include concise text explanations and clearly cite your data sources.
6. Review and Refine: Check for accuracy, clarity, and visual appeal.

Measures of Central Tendency

Measures of central tendency are statistical values that describe the center or typical value of a set of data. They help to summarize a large amount of data into a single, representative value, making it easier to understand the overall characteristics of the data set.

Types of Measures of Central Tendency

The three main types of measures of central tendency are:

1. Mean: The arithmetic average of a data set.
2. Median: The middle value in an ordered data set.
3. Mode: The most frequently occurring value in a data set.

The Mean (Arithmetic Mean)

The mean is calculated by summing all the values in a data set and dividing by the number of values. It is the most commonly used measure of central tendency.

Formula

(bar{x} = frac{sum x}{n})

Where:

1. (bar{x}) = Mean
2. (sum x) = Sum of all values in the data set
3. (n) = Number of values in the data set

Example 1

Question: A small business recorded the daily sales (in Naira) for a week as: ₦5,000, ₦7,500, ₦6,000, ₦8,000, ₦5,500, ₦7,000, ₦6,500. Calculate the mean daily sales.

Solution:

Step 1: Write the formula.

(bar{x} = frac{sum x}{n})

Step 2: Sum the values and count the number of values.

(sum x = 5000 + 7500 + 6000 + 8000 + 5500 + 7000 + 6500 = 45500)

(n = 7)

Step 3: Substitute the values and calculate.

(bar{x} = frac{45500}{7})

(bar{x} = 6500)

Answer: The mean daily sales is ₦6,500.

The Median

The median is the middle value of a data set when the values are arranged in ascending or descending order. It is less affected by extreme values (outliers) than the mean.

How to Find the Median

1. Order the Data: Arrange all values in ascending or descending order.
2. Find the Middle Value:
   • If (n) (number of values) is odd, the median is the single middle value. Its position is (frac{n+1}{2}).
   • If (n) is even, the median is the average of the two middle values. Their positions are (frac{n}{2}) and (frac{n}{2} + 1).

Example 1

Question: Find the median of the following number of siblings reported by students: 3, 1, 5, 2, 4, 1, 3.

Solution:

Step 1: Order the data in ascending order.

1, 1, 2, 3, 3, 4, 5

Step 2: Count the number of values ((n)).

(n = 7)

Step 3: Since (n) is odd, the median is the middle value. Position = (frac{7+1}{2} = 4^{th}) position.

The 4th value in the ordered list is 3.

Answer: The median number of siblings is 3.

Example 2

Question: Find the median of the following monthly incomes (in thousands of Naira) for a small sample of workers: ₦45, ₦60, ₦30, ₦70, ₦55, ₦40.

Solution:

Step 1: Order the data in ascending order.

30, 40, 45, 55, 60, 70

Step 2: Count the number of values ((n)).

(n = 6)

Step 3: Since (n) is even, the median is the average of the two middle values. Positions are (frac{6}{2} = 3^{rd}) and (frac{6}{2} + 1 = 4^{th}).

The 3rd value is 45. The 4th value is 55.

Median = (frac{45 + 55}{2} = frac{100}{2} = 50)

Answer: The median monthly income is ₦50,000.

The Mode

The mode is the value that appears most frequently in a data set. A data set can have one mode (unimodal), more than one mode (multimodal), or no mode if all values appear with the same frequency.

How to Find the Mode

1. Count Frequencies: Tally the occurrences of each value in the data set.
2. Identify Most Frequent: The value(s) with the highest frequency is the mode.

Example 1

Question: The prices (in Naira) of a particular brand of bread sold in different shops are: ₦400, ₦450, ₦400, ₦500, ₦450, ₦400, ₦550. Find the mode of the prices.

Solution:

Step 1: List the values and their frequencies.

1. ₦400 appears 3 times
2. ₦450 appears 2 times
3. ₦500 appears 1 time
4. ₦550 appears 1 time

Step 2: Identify the value with the highest frequency.

The price ₦400 appears most frequently (3 times).

Answer: The mode of the prices is ₦400.

Example 2

Question: A survey of household sizes in a community yielded the following data: 4, 5, 3, 6, 4, 5, 7, 4, 5, 8. Find the mode.

Solution:

Step 1: List the values and their frequencies.

1. 3 appears 1 time
2. 4 appears 3 times
3. 5 appears 3 times
4. 6 appears 1 time
5. 7 appears 1 time
6. 8 appears 1 time

Step 2: Identify the value(s) with the highest frequency.

Both 4 and 5 appear 3 times, which is the highest frequency.

Answer: The modes are 4 and 5 (bimodal).

Teaching Methods/Instructional Techniques

Discussion, Demonstration, Guided Practice, Question and Answer, Explanation, Group Work, Practical Activity, Problem Solving

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Questioning/Recall

Teacher’s Activity: The teacher greets the students and asks them to recall previous lessons on data collection and presentation. The teacher then introduces the topic by asking how they think complex data can be presented simply and visually.

Pupils’ Activity: Pupils respond to questions and share ideas on data presentation.

Learning Point: Data presentation overview

Step 2: Introduction to Infographics

Time: 10 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher explains what infographics are, their purpose, and their importance in economics using simple examples (e.g., showing population growth, market share, or budget allocation visually). The teacher may show a simple infographic example.

Pupils’ Activity: Pupils listen attentively, ask questions, and observe the infographic examples.

Learning Point: Meaning of infographics

Step 3: Creating Infographics

Time: 10 minutes

Teaching Skill: Guided Practice/Demonstration

Teacher’s Activity: The teacher guides students to form groups and, using electronic devices and internet access, instructs them to explore tools like Canva or Google Slides to understand how infographics are designed. The teacher emphasizes the elements of a good infographic and how to use raw data (e.g., collected from online sources on local market prices) to create a simple visual representation.

Pupils’ Activity: Pupils work in groups, explore design tools, and discuss how to represent economic data visually. They begin planning a simple infographic.

Learning Point: Infographic design principles

Step 4: Introduction to Measures of Central Tendency

Time: 5 minutes

Teaching Skill: Explanation

Teacher’s Activity: The teacher introduces the concept of measures of central tendency, explaining their role in summarizing data. The teacher lists the three main types: Mean, Median, and Mode, and briefly defines each.

Pupils’ Activity: Pupils listen and take initial notes on the definitions of mean, median, and mode.

Learning Point: Central tendency concepts

Step 5: Computing the Mean

Time: 10 minutes

Teaching Skill: Problem Solving/Guided Practice

Teacher’s Activity: The teacher explains the formula for calculating the mean. The teacher then guides students, in their groups, to collect data (e.g., number of siblings/relatives in their families) and create a frequency distribution table. The teacher then demonstrates how to calculate the mean from this data, using the provided example from the Board Summary.

Pupils’ Activity: Pupils collect data, create frequency tables, and practice calculating the mean under the teacher’s guidance.

Learning Point: Mean calculation practice

Step 6: Computing the Median and Mode

Time: 10 minutes

Teaching Skill: Problem Solving/Guided Practice

Teacher’s Activity: The teacher explains how to find the median (ordering data, identifying middle value) and the mode (most frequent value). Using the same data collected by the groups or new simple economic data sets, the teacher guides students through calculating the median and mode, providing worked examples from the Board Summary.

Pupils’ Activity: Pupils practice calculating the median and mode for their collected data or given data sets.

Learning Point: Median and mode computation

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. What is an infographic?
2. Mention two elements of a good infographic.
3. List the three measures of central tendency.
4. Given the data set: 10, 12, 8, 10, 15, calculate the mean.
5. From the data set in question 4, what is the mode?

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Infographics and central tendency understanding

Step 8: Note-Taking

Time: 10 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes on infographics, their importance, and the calculation of mean, median, and mode into their notebooks.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Recording lesson content

Step 9: Conclusion

Time: 5 minutes

Teaching Skill: Consolidation

Teacher’s Activity: The teacher summarizes the key points of the lesson, reiterating the importance of infographics for visual data presentation and measures of central tendency for summarizing economic data. The teacher encourages students to apply these tools in understanding real-world economic scenarios.

Pupils’ Activity: Pupils listen and ask any final clarifying questions.

Learning Point: Lesson summary and application

Continuous Assessment/Further Study

Type: Homework/Group Work

Instruction: In your groups, collect data on the monthly electricity bills (in Naira) of 10 households in your community for the last month. Then:

1. Calculate the mean, median, and mode of the collected electricity bills.
2. Using Canva or Google Slides, design a simple infographic to visually represent your findings, highlighting the average bill and any interesting patterns.
3. Present your infographic and findings to the class next week.

Lesson Keywords

• Infographics – Visual representations of information, data, or knowledge.
• Data Visualization – The graphical representation of information and data.
• Measures of Central Tendency – Statistical values that describe the center or typical value of a data set.
• Mean – The arithmetic average of a data set.
• Median – The middle value in an ordered data set.
• Mode – The most frequently occurring value in a data set.
• Raw Data – Data that has not yet been processed or analyzed.

Differentiation

For students who need support: Provide simpler, smaller data sets for calculating central tendency. Offer pre-designed infographic templates or more direct guidance on using design tools. Pair them with more proficient students for group activities.

For students who need enrichment: Challenge them to analyze a larger, more complex economic data set (e.g., national inflation rates over a year) and create a detailed infographic comparing different economic indicators. Encourage them to research other types of data visualization tools.

Suggested Lesson Videos

YouTube search for “infographics for economics ss1”
YouTube search for “measures of central tendency economics ss1”