Class: Senior Secondary School 1 (SS 1)
Term: Second Term
Week: 9
Age: 15 years
Duration: 45 minutes
Subject: Block Laying, Brick Laying and Concrete Work
Curriculum Theme: Entrepreneurship (Trade Subjects)
Previous Lesson: Maintenance of Concreting Tools and Equipment.
Topic: CONCRETING
Subject Matter: Definition of concrete, components of concrete, materials for concrete, mixing ratios

Specific Objectives

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

Cognitive Domain:

Define concrete.
List the components of concrete.
State the materials used for concrete.
Explain different mixing ratios of concrete.

Affective Domain:

Appreciate the importance of correct concrete mixing in construction.
Develop an interest in practical concrete work.

Psychomotor Domain:

Identify the various materials used in concrete production.
Calculate simple concrete mixing ratios for different purposes.

Collaborate effectively in group discussions on concrete properties and uses.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Block Laying, Brick Laying and Concrete Work.
State Unified Scheme of Work for Senior Secondary Schools.
Building Construction for Senior Secondary Schools by J. O. Popoola.
https://waeconline.org.ng/
https://nerdc.gov.ng/

Instructional Materials

The teacher will teach this lesson with the aid of:

Samples of cement, sand, gravel (coarse aggregate).
Water.
Measuring box/bucket.
Trowel and shovel.
A chart illustrating concrete mixing ratios.

Rationale for the Lesson

This lesson helps pupils understand a fundamental aspect of building construction, which is concrete. Knowing how concrete is made and mixed correctly enables pupils to appreciate its role in construction and provides a foundational skill for potential careers in building trades.

Prerequisite/Previous Knowledge

Pupils should have basic knowledge of common building materials and their uses.

Lesson Content/Board Summary

CONCRETING

Definition of Concrete

Concrete is a composite construction material made from a mixture of cement, aggregates (sand and gravel), and water. It hardens over time to form a strong, durable, stone-like material used widely in buildings, roads, and other structures.

Components of Concrete

The main components that make up concrete are:

Cement
Fine aggregate (sand)
Coarse aggregate (gravel or crushed stone)
Water
Admixtures (optional, for special properties)

Materials for Concrete

The specific materials used to produce concrete include:

Cement: A binding material, usually Portland cement.
Sand: Fine aggregate, typically sharp and clean.
Gravel/Crushed Stone: Coarse aggregate, clean and free from impurities.
Water: Clean, potable water suitable for drinking.

Mixing Ratios for Concrete

Mixing ratios specify the proportions of cement, sand, and gravel, usually followed by water, to achieve desired concrete strength. These ratios are typically given in parts by volume (e.g., 1:2:4 means 1 part cement, 2 parts sand, 4 parts gravel).

Common mixing ratios for various purposes are:

1:2:4: Used for general concrete work, foundations, and reinforced concrete. (Strong mix)
1:3:6: Used for mass concrete, non-structural elements, and blinding. (Medium mix)
1:4:8: Used for lean concrete, sub-bases, and filling. (Weak mix)

The amount of water added affects the workability and strength of the concrete. Too much water reduces strength.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils and reviews the previous lesson briefly. The teacher then introduces the new topic, “CONCRETING,” by asking pupils to mention structures they know that are made of concrete, like floors or pillars.
Pupils’ Activity: Pupils respond to the teacher’s questions and listen attentively to the introduction.
Learning Point: Pupils are prepared for the lesson and connect it to their environment.

Step 2: Definition of Concrete

Time: 7 minutes
Teaching Skill: Explanation/Definition
Teacher’s Activity: The teacher defines concrete clearly, explaining that it is a mixture of cement, aggregates, and water that hardens. The teacher writes the definition on the board.
Pupils’ Activity: Pupils listen, take notes, and ask questions for clarification.
Learning Point: Pupils understand the definition of concrete.

Step 3: Components of Concrete

Time: 7 minutes
Teaching Skill: Listing/Identification
Teacher’s Activity: The teacher lists and explains the main components of concrete, showing samples of cement, sand, and gravel if available. The teacher also mentions water as an essential component.
Pupils’ Activity: Pupils observe the samples, listen to explanations, and identify the components.
Learning Point: Pupils can identify and name the components of concrete.

Step 4: Materials for Concrete

Time: 7 minutes
Teaching Skill: Explanation/Demonstration
Teacher’s Activity: The teacher elaborates on each material (cement, sand, gravel, water), explaining their individual roles in concrete production. The teacher emphasizes the importance of using clean and quality materials.
Pupils’ Activity: Pupils listen, take notes, and ask questions regarding the quality of materials.
Learning Point: Pupils understand the specific materials needed and their characteristics.

Step 5: Mixing Ratios for Concrete

Time: 7 minutes
Teaching Skill: Explanation/Calculation
Teacher’s Activity: The teacher explains the concept of mixing ratios (e.g., 1:2:4) and their significance for different construction purposes. The teacher provides examples of common ratios and what they are used for, using a chart if available.
Pupils’ Activity: Pupils listen, observe the chart, and understand how ratios are applied.
Learning Point: Pupils grasp the concept of concrete mixing ratios and their applications.

Step 6: Practical Demonstration/Discussion

Time: 5 minutes
Teaching Skill: Demonstration/Application
Teacher’s Activity: The teacher briefly demonstrates or describes the process of mixing concrete using the samples and tools, emphasizing safety and correct proportioning. The teacher encourages pupils to discuss how incorrect mixing could affect a structure.
Pupils’ Activity: Pupils observe, ask questions about the mixing process, and participate in the discussion.
Learning Point: Pupils gain insight into the practical application of concrete mixing.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

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

Define concrete in your own words.
List any three components of concrete.
State two common materials used to make concrete.
Mention one common mixing ratio for general concrete work.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 2 minutes
Teaching Skill: Summarization/Assignment
Teacher’s Activity: The teacher summarizes the key points of the lesson, reiterating the definition, components, materials, and importance of correct mixing ratios for concrete. The teacher then gives homework: “Research other types of aggregates used in concrete production.”
Pupils’ Activity: Pupils listen to the summary and copy the homework assignment.
Learning Point: Pupils consolidate their learning and are given a task for further study.

Lesson Keywords

Concrete – A composite building material made from cement, aggregates, and water.
Cement – A binding powder that hardens when mixed with water.
Aggregate – Granular materials like sand and gravel used in concrete.
Sand – Fine aggregate used in concrete.
Gravel – Coarse aggregate used in concrete.
Mixing Ratio – The proportion of cement, sand, and gravel used in concrete.

Differentiation

To cater to diverse learners, the teacher will use visual aids like charts and actual material samples for visual learners. Group discussions will be encouraged for kinesthetic and social learners. For pupils who need more support, the teacher will provide simplified explanations and one-on-one assistance. Advanced learners will be challenged with additional questions about concrete properties and applications.

Note for teachers using this lesson plan

Teachers should ensure all materials are available for demonstration, even if it’s just small samples. Emphasize safety precautions if any practical mixing is attempted. Encourage pupils to ask questions and relate the lesson to real-life construction examples they see around them.