Introduction to Graphs – Elements and Types

Grade 6 · Mathematics

Semester 2 | Period 6 | Week 34

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Subject: Mathematics

Semester: 2

Period: 6

Week: 34

School Name:
Teacher’s Name:
Subject: Mathematics
Grade Level: Grade 6
Date: Week 34
Lesson Duration: 45 minutes
Week & Period: Week 34, Period 6
Topic: Introduction to Graphs – Elements and Types
Sub-topic: Bar Graphs, Line Graphs, Pictographs, and Pie Charts

Learning Objectives
By the end of the lesson, students should be able to:
Define graphs as visual representation of data
Identify the elements of a graph (title, labels, scale, axis, key/legend)
List types of graphs and state their uses
Differentiate between bar graph, pictograph, line graph, and pie chart

Previous Knowledge
Students already know how to organize data in tables.

Instructional Materials
Mathematics textbook for Grade 6

Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher shows a simple bar graph of class attendance and asks learners what information it shows.

B – Building Knowledge (Main Lesson Body)

Time: 25–30 minutes

Drawing Bar Graphs

  • A bar graph is drawn from a frequency table.
  • Steps:
  1. Draw two axes (horizontal x-axis for categories, vertical y-axis for frequency).
  2. Choose a suitable scale (e.g., 1 cm = 5 students).
  3. Draw rectangular bars for each category with equal width but varying height.
  4. Label the axes, bars, and give the graph a title.
  • Example: A class has 20 boys and 15 girls. Draw a bar graph.
    • Scale: 1 cm = 5 pupils.
    • Boys bar = 20 pupils = 4 cm tall.
    • Girls bar = 15 pupils = 3 cm tall.

 

Drawing Pictographs (Picture Graphs)

  • A pictograph uses symbols or pictures to represent data values.
  • Steps:
  1. Choose a symbol (e.g., 1 apple picture = 5 students).
  2. Count how many symbols are needed for each category.
  3. Draw symbols in rows for each category.
  • Example: Favorite fruits survey: Mango – 10, Apple – 15, Orange – 20.
    • If 1 fruit picture = 5 students:
    • Mango = 2 pictures, Apple = 3 pictures, Orange = 4 pictures.

 

Drawing Line Graphs

  • A line graph shows changes or trends over time.
  • Steps:
  1. Draw axes (x-axis = time, y-axis = data values).
  2. Plot points using the data.
  3. Connect the points with straight lines.
  4. Title and label the axes.
  • Example: School enrollment:
    • 2018 – 100 students, 2019 – 120, 2020 – 140, 2021 – 130, 2022 – 150.
    • Plot and connect to show trend.

 

Drawing Pie Charts (Circular Graphs)

  • A pie chart represents data as parts of a circle (360°).
  • Steps:
  1. Add all data values to get the total.
  2. Find each category’s angle:
    Angle=Category value/Total × 360∘
  3. Draw a circle with a compass.
  4. Use a protractor to draw sectors.
  5. Shade or label each sector clearly.
  • Example: Students’ favorite sport: Football – 90, Basketball – 60, Tennis – 30.
    • Total = 180.
    • Football: (90 ÷ 180 × 360°) = 180°.
    • Basketball: (60 ÷ 180 × 360°) = 120°.
    • Tennis: (30 ÷ 180 × 360°) = 60°.

 

Interpretation of Graphs

  • To interpret a graph means to read and understand what it is showing.
  • Examples:
  1. From a bar graph of exam scores, find which subject had the highest score.
  2. From a line graph of rainfall, see in which month rainfall was lowest.
  3. From a pie chart, calculate percentage of pupils who like a certain sport.

 

Learners’ Activities (Expanded)

  • In groups, learners draw bar graphs from classroom data (e.g., boys vs girls, shoe sizes, favorite colors).
  • Learners use given data to draw all four types of graphs (bar, pictograph, line, pie).
  • Learners exchange graphs with classmates and practice interpreting each other’s graphs.
  • Learners practice converting the same data set into different graphs (e.g., exam results shown as bar graph, pie chart, and line graph).

 

Assessment Checks

  1. Teacher gives data: Boys = 18, Girls = 12. Learners draw a bar graph.
  2. A survey shows: Rice – 40 pupils, Beans – 20 pupils, Yam – 10 pupils. Teacher asks learners to draw a pictograph (1 picture = 10 pupils).
  3. From a line graph of rainfall (Jan – 50 mm, Feb – 40 mm, Mar – 80 mm), learners identify which month had the least rainfall.
  4. Teacher asks: “What is the central angle for 50 students out of 200 in a pie chart?” (Answer: 90°).
  5. Learners interpret a graph shown by the teacher: “Which subject had the lowest marks? How many students chose football compared to tennis?”

 

Notes (Expanded & Detailed)

  • Graphs are drawn from datasets and must include title, scale, labels, and key for clarity.
  • Bar graphs and pictographs are easiest for beginners; line graphs and pie charts are useful for more complex data.
  • Pie charts require conversion of frequencies into angles using 360°.
  • Interpretation means reading values, comparing categories, and analyzing trends.
  • Practical relevance: Graphs are widely used in newspapers, schools, health reports, and businesses to show data in a simple way.

C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Graphs make data easy to understand. Bar, pictograph, line, and pie charts are the common types.

Evaluation Method (Expanded):
Exit slip/quiz: Name two elements of a graph and one type of graph with its use. Teacher will collect slips and provide oral feedback.

Assignment (Expanded):
Draw a simple bar graph of the number of boys and girls in your class.

Follow-up Activity:
Learners look for graphs in newspapers and bring to class.

Differentiation / Inclusive Strategies
Provide simple pictographs for weak learners. Let advanced learners compare multiple graph types.

Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low