Lesson Notes By Weeks and Term v3 - Primary 2
Area
Download the Lessonotes Mobile Nigeria 2025 app for faster lesson access on Android and iPhone.
Area
Download the Lessonotes Mobile Nigeria 2025 app for faster lesson access on Android and iPhone.
Subject: General Mathematics
Class: Primary 2
Term: 1st Term
Week: 10
Theme: Mensuration And Geometry
This page supports the lesson note with a companion video and a short classroom-ready summary.
For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.
Watch on YouTubecompare are as of surfaces; identify the use of standard measuring units;
Materials: Various flat surfaces (e.g., textbook, exercise book, tray, floor tile, blackboard, desk surface, piece of fabric, larger mat) Non-standard units (e.g., identical leaves, identical playing cards, identical small paper cut-outs, matchboxes, palm prints traced on paper) Pre-cut identical square paper units (representing standard units, e.g., 2cm x 2cm squares) Masking tape or chalk to outline surfaces if needed Worksheets with simple grids for counting squares Teacher Activities: Introduction (10 minutes): Begin by asking pupils to identify which object takes up more space between two common classroom items (e.g., a textbook and an exercise book). Introduce the term "Area" as the amount of surface an object covers. Display two contrasting flat surfaces (e.g., a large tray and a small book). Ask pupils to guess which one has a larger area.
Demonstration: Comparing Area with Non-Standard Units (15 minutes): Select a common non-standard unit (e.g., identical leaves or small paper cut-outs). Demonstrate covering the first surface (e.g., a textbook) completely with the chosen units, ensuring no overlaps and no gaps. Count aloud as units are placed. Record the number of units used for the first surface. Repeat the process for the second surface (e.g., an exercise book) using the same non-standard units. Record the number of units used for the second surface. Compare the two counts and conclude which surface has a larger/smaller area. Emphasize that more units mean a larger area.
Guided Practice: Student Comparison (20 minutes): Divide the class into small groups (3-4 pupils per group). Provide each group with two different flat surfaces (e.g., a larger tray and a smaller tray, or a table top and a chair seat) and a supply of identical non-standard units (e.g., playing cards, matchboxes). Instruct groups to work together to cover each surface and count the units. Circulate among groups, providing assistance, asking guiding questions (e.g., "Are your units overlapping?", "Are there any gaps?", "Which one took more units?"). Have each group report their findings to the class, stating which surface has a larger/smaller area and why. Introduction to Standard Units (15 minutes): Facilitate a discussion about the challenges of using non-standard units (e.g., "What if your group used different-sized leaves from another group? Would you get the same answer?"). Lead them to understand the need for units that are always the same size, which are called "standard units." Introduce pre-cut identical square paper units. Explain that these are like "square units," which are used to measure area because they are all the same size. Demonstrate covering a small surface (e.g., a small book or a marked-out rectangle on the desk) with these identical square units. Count the squares and state the area in "square units." Application: Using Standard Units (10 minutes): Provide each group with a small pre-drawn shape on paper (e.g., a simple rectangle or L-shape) and a supply of the identical square paper units. Instruct them to cover the shape with the square units and count them. Alternatively, provide worksheets with simple shapes drawn on a grid (where each grid square represents one standard unit). Pupils count the squares within the shapes.
Student Activities: Observation and Participation: Pupils actively observe the teacher's demonstrations and participate in discussions.
Group Work (Hands-on Comparison): In groups, pupils select a non-standard unit. They work together to cover two given surfaces completely and count the units for each. They compare the counts and identify which surface has a larger/smaller area. Groups present their findings to the class.
Practical Application (Standard Units): Pupils use identical square paper units to cover small given shapes or areas. They count the number of square units used to determine the area. They practice counting squares on grid paper to find the area of simple shapes.
Discussion: Pupils engage in discussions about the importance of using identical units for fair and accurate comparison. The teacher guides pupils through these questions, ensuring they understand the process before moving to independent practice.
Question 1: A farmer wants to plant vegetables. He has two small plots of land. Plot A can be covered by 25 identical small stones. Plot B can be covered by 18 identical small stones. Which plot has a larger area for planting?
Solution: Plot A uses 25 stones. Plot B uses 18 stones. Since 25 is greater than 18, Plot A uses more stones.
Answer: Plot A has a larger area for planting.
Commentary:* This question directly assesses the comparison of areas using non-standard units. The context is relatable to Nigerian farming communities.
Question 2: Look at the two shapes drawn below. Each small square is 1 standard unit.
Shape X: ``` _ _ _ |X|X|X| |_|_|_| |X|X|X| |_|_|_| ``` Shape Y: ``` _ _ _ _ |Y|Y|Y|Y| |_|_|_|_| |Y|Y|Y|Y| |_|_|_|_| |Y|Y|Y|Y| |_|_|_|_| ``` a) What is the area of Shape X in standard units? b) What is the area of Shape Y in standard units? c) Which shape has a smaller area?
Solution: a)
Count the squares in Shape X: 6 squares. So, the area of Shape X is 6 standard units. b)
Count the squares in Shape Y: 12 squares. So, the area of Shape Y is 12 standard units. c) Comparing 6 and 12, 6 is smaller.
Answer: Shape X has a smaller area.
Commentary:* This question assesses the identification of area using standard units (grid squares) and then comparing them.
Question 3: A tailor needs to cut two pieces of fabric. Piece P requires 7 identical square-shaped patterns to cover it. Piece Q requires 9 identical square-shaped patterns to cover it. a) What is the area of Piece P in square patterns? b) What is the area of Piece Q in square patterns? c) Which piece of fabric has a larger area?
Solution: a) The area of Piece P is 7 square patterns. b) The area of Piece Q is 9 square patterns. c) Comparing 7 and 9, 9 is larger.
Answer: Piece Q has a larger area.
Commentary:* This reinforces the concept of area using 'square patterns' as a form of standard unit and requires direct comparison. The tailoring context is relevant.
Question 4: Explain why it is better to use identical square tiles (standard units) to measure the floor of a room instead of using different-sized sandals (non-standard units).
Solution: It is better to use identical square tiles because: Consistency: All the tiles are the same size, so everyone who measures the floor will get the same answer.
Fairness/Accuracy: Using different-sized sandals means different people will get different answers, which is not fair or accurate, especially if you are buying tiles or flooring materials.
Commentary:* This question directly targets the second performance objective, emphasizing the understanding of why standard units are important for consistent and accurate measurement. To compare the areas of two or more surfaces, learners can use non-standard units. These are objects of arbitrary size that can be used to cover a surface. Examples include leaves, small pieces of paper (cut to be identical), playing cards, matchboxes, or even a pupil's handprint.
Concept Explanation: When comparing two surfaces, the surface that requires more of the same non-standard units to cover it completely has a larger area. Conversely, the surface requiring fewer units has a smaller area.
Step-by-Step Reasoning for Comparison: Select a Non-Standard Unit: Choose a single type of object (e.g., identical leaves, or identical small paper squares).
Cover the First Surface: Carefully place the chosen non-standard units on the first surface without overlapping and without leaving gaps.
Count the Units: Count how many units were used to cover the first surface. Record this number.
Cover the Second Surface: Repeat the process for the second surface using the exact same type and size of non-standard unit.
Count the Units: Count how many units were used for the second surface. Record this number.
Compare the Counts: The surface with the higher count of non-standard units has the larger area.
Worked Example 1 (Nigerian Context): Comparing Mat Sizes Scenario: A mother wants to know which mat, Mat A or Mat B, is larger to lay on the floor for children to sleep. She uses identical pieces of fabric (non-standard units).
Steps: Mat A is covered by carefully placing 15 identical pieces of fabric. Mat B is covered by carefully placing 10 identical pieces of fabric.
Comparison: Since Mat A required 15 pieces and Mat B required 10 pieces, and 15 is greater than 10, Mat A has a larger area than Mat
B. Conclusion: Mat A can accommodate more children or provide more sleeping space.
For Struggling Learners: Simplified Units: Provide larger non-standard units (e.g., large paper cut-outs, full handprints) for easier counting and fewer units required to cover.
Direct Instruction: Offer one-on-one guidance during practical activities, verbally guiding them through the steps of covering and counting.
Visual Aids: Use highly contrasting objects for comparison (e.g., a very small book vs. a very large tray) to make the difference in area more obvious.
Pre-drawn Outlines: Provide surfaces with pre-drawn outlines of where to place units to minimize errors in placement.
For High-Achieving Learners: Estimation Challenge: Challenge them to estimate the area of a surface before covering it with units, and then compare their estimate to the actual count.
Irregular Shapes: Provide shapes with slightly irregular boundaries and ask them to determine the area as best as possible using the standard square units, discussing how to handle partial squares.
Different Unit Sizes Discussion: Ask them to explore what happens if they use smaller square units vs. larger square units for the same surface, leading to an understanding that the number of units changes, but the actual area remains the same.
Problem-Solving: Present scenarios where they need to choose the most appropriate unit for measuring a very large surface (e.g., a football field) or a very small one (e.g., a stamp), encouraging critical thinking about scale.
Agriculture and Land Use: Farmers in Nigeria often compare the sizes of different plots of land for planting various crops (e.g., deciding which plot is larger for growing cassava vs. maize). Understanding area helps them estimate yield or plan irrigation. This lesson provides the foundation for comparing these land sizes, even if informally.
Home Management and Construction: At home, people compare the area of mats for sleeping, or the surface area of tables for eating. In construction, understanding area is essential for deciding how many floor tiles are needed for a room or how much paint is required for a wall. This topic helps pupils understand "how much space" needs to be covered.
Market and Trade: Market traders compare the surface area of their stalls to understand how much space they have to display goods. Customers might compare the surface area of different pieces of fabric to determine which offers more material, even if informally, before standard units like meters are introduced. This lesson lays the groundwork for such comparisons.