Class: Senior Secondary School 1 (SSS 1)
Term: Second Term
Week: 9
Age: 15 years
Duration: 45 minutes
Subject: Carpentry And Joinery
Curriculum Theme: Entrepreneurship Trade Subjects
Previous Lesson: Other types of manufactured boards.
Topic: SOURCES AND PRODUCTS OF TIMBER – Manufactured Board (Plywood)
Subject Matter: types of plywood, uses of plywood, structure of plywood

Specific Objectives

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

Cognitive Domain:

Define plywood.
Describe the structure of plywood.
List different types of plywood.
State various uses of plywood.

Affective Domain:

Appreciate the importance of plywood as a versatile building material.
Develop an interest in identifying different types of plywood.

Psychomotor Domain:

Sketch different plywood types.
Identify various plywood samples.

Collaborate with peers to discuss the applications of plywood in daily life.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Technical Colleges.
State Unified Scheme of Work for Senior Secondary Schools.
Basic Woodwork for Senior Secondary Schools by A.O. Akinola.
Online resources on woodworking and manufactured boards.

Instructional Materials

The teacher will teach this lesson with the aid of:

Plywood samples (e.g., marine, exterior, interior).
Charts showing the structure of plywood.
Pictures or diagrams illustrating different types and uses of plywood.

Rationale for the Lesson

Understanding plywood is important because it is a widely used material in construction, furniture making, and various other industries. This lesson helps pupils to know the different kinds of plywood and their appropriate applications, which is useful for practical skills and future career paths in carpentry and joinery.

Prerequisite/Previous Knowledge

Pupils have basic knowledge of timber and other manufactured boards from previous lessons.

Lesson Content/Board Summary

SOURCES AND PRODUCTS OF TIMBER – Manufactured Board (Plywood)

Definition of Plywood

Plywood is a type of manufactured board made from thin sheets of wood veneer, called plies, which are glued together with adjacent layers having their wood grain rotated up to 90 degrees to one another. It is an engineered wood product that offers high strength and stability.

Structure of Plywood

Plywood consists of several layers of wood veneer that are bonded together using adhesives under heat and pressure. The key features of its structure include:

Veneers (Plies): These are thin sheets of wood peeled from logs.
Grain Direction: The grain of alternate plies is laid perpendicular to each other to increase strength and reduce shrinkage.
Core: The central layer(s) of veneer.
Face and Back Veneers: The outermost layers that provide the finished surface.
Adhesive: Strong glues (e.g., urea-formaldehyde, phenol-formaldehyde) are used to bond the veneers together.

Types of Plywood

Plywood is classified based on its intended use, adhesive type, and resistance to moisture. The following are common types of plywood:

Interior Plywood: Made with less water-resistant glue, suitable for indoor applications where moisture exposure is minimal (e.g., furniture, wall paneling).
Exterior Plywood: Uses water-resistant adhesives (like phenolic resin) and is suitable for outdoor use where it may be exposed to some moisture (e.g., sheathing, siding).
Marine Plywood: Highly water-resistant, made with waterproof glue and void-free core layers, ideal for boat building and other high-moisture environments.
Structural Plywood: Designed for strength and rigidity, often used in framing, subflooring, and roof sheathing.
Aircraft Plywood: Very high-quality, thin, and strong plywood made from select hardwoods, used where lightness and strength are essential.

Uses of Plywood

Plywood is a versatile material used in various applications due to its strength, stability, and relatively low cost. The following are common uses of plywood:

Furniture making (cabinets, shelves, tables).
Construction (subflooring, wall sheathing, roofing).
Interior decoration (wall paneling, ceiling).
Boat building (marine plywood).
Formwork for concrete casting.
Packaging and crates.
Toys and crafts.
Vehicle interiors.

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, reviews the previous lesson on other types of manufactured boards, and introduces the topic of plywood by asking pupils if they have seen or used plywood before.
Pupils’ Activity: Pupils respond to greetings, recall points from the previous lesson, and share their experiences with plywood.
Learning Point: Pupils connect previous knowledge to the new topic and are prepared for the lesson.

Step 2: Definition of Plywood

Time: 7 minutes
Teaching Skill: Explanation/Definition
Teacher’s Activity: The teacher defines plywood, explaining that it is an engineered wood product made from thin layers of wood veneer glued together. The teacher emphasizes the perpendicular grain direction of adjacent layers.
Pupils’ Activity: Pupils listen attentively, take notes, and ask questions for clarification.
Learning Point: Pupils understand the definition of plywood.

Step 3: Structure of Plywood

Time: 7 minutes
Teaching Skill: Demonstration/Explanation
Teacher’s Activity: The teacher uses a plywood sample and a chart to explain the layered structure of plywood, pointing out the veneers, core, face, back, and the role of the adhesive and perpendicular grain arrangement.
Pupils’ Activity: Pupils observe the samples and charts, listen to the explanation, and note the key components of plywood structure.
Learning Point: Pupils comprehend the structural composition of plywood.

Step 4: Types of Plywood

Time: 8 minutes
Teaching Skill: Categorization/Illustration
Teacher’s Activity: The teacher explains and describes different types of plywood such as interior, exterior, marine, and structural plywood, highlighting their distinguishing features and suitable applications. Samples of different types are shown where available.
Pupils’ Activity: Pupils listen, observe the samples, and identify the characteristics that differentiate the types of plywood.
Learning Point: Pupils can differentiate between various types of plywood.

Step 5: Uses of Plywood

Time: 7 minutes
Teaching Skill: Discussion/Brainstorming
Teacher’s Activity: The teacher leads a discussion on the various uses of plywood, encouraging pupils to mention common applications they have observed in their homes or communities. The teacher supplements their responses with other uses.
Pupils’ Activity: Pupils actively participate in the discussion, listing and explaining different uses of plywood.
Learning Point: Pupils know the wide range of applications for plywood.

Step 6: Practical Activity

Time: 6 minutes
Teaching Skill: Practical Application/Observation
Teacher’s Activity: The teacher provides paper and pencils for pupils to sketch simple diagrams illustrating the layered structure of plywood or encourages them to closely examine the provided plywood samples and identify their potential types.
Pupils’ Activity: Pupils attempt to sketch the structure of plywood or identify different types based on the samples provided.
Learning Point: Pupils practice visual identification and representation of plywood concepts.

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 plywood in your own words.
Describe the basic structure of plywood.
Mention three types of plywood.
List four common uses of plywood.

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
Teacher’s Activity: The teacher summarizes the key points of the lesson, reiterating the definition, structure, types, and uses of plywood. The teacher then assigns homework for pupils to research other manufactured boards.
Pupils’ Activity: Pupils listen to the summary and copy down the homework.
Learning Point: Pupils consolidate their learning and are prepared for further study.

Lesson Keywords

Plywood – A manufactured board made from thin wood veneers glued together.
Veneer – A thin slice of wood used as a layer in plywood.
Ply – A single layer of veneer in plywood.
Grain Direction – The orientation of wood fibers in a veneer.
Adhesive – The glue used to bond veneers in plywood.
Marine Plywood – A type of plywood resistant to moisture, suitable for boats.

Differentiation

For struggling learners, the teacher will provide simplified diagrams and allow more time for hands-on examination of plywood samples. Advanced learners will be challenged to research the manufacturing process of plywood or compare the properties of plywood with other manufactured boards like MDF or particleboard.

Note for teachers using this lesson plan

Teachers should ensure they have various plywood samples available for demonstration to enhance pupils’ understanding. Encourage pupils to bring pictures of items made from plywood from their homes or communities. Emphasize safety precautions when handling wood materials and tools, even during theoretical discussions.