Exploring Quadrilaterals: Types, Properties, and Constructions in Technical Drawing SS 1 First Term Lesson Notes Week 11

Technical Drawing, SS 1, First Term, Week 11 on Quadrilaterals.

Lesson Plan: Quadrilaterals

Subject: Technical Drawing
Class: SS 1
Term: First Term
Week: 11
Age: 14-16 years
Topic: Quadrilaterals
Sub-Topic: Types and Construction of Quadrilaterals
Duration: 40 minutes

Behavioral Objectives

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

1. Describe the properties of different types of quadrilaterals.
2. Recognize and identify quadrilateral-shaped objects in the classroom.
3. Construct various types of quadrilaterals using given measurements.

Keywords

• Quadrilateral
• Rectangle, square, parallelogram, rhombus, trapezium
• Opposite sides, parallel, right angle
• Diagonals, symmetry

Set Induction

The teacher will begin the lesson by showing common classroom objects (e.g., books, whiteboards, tables) that have quadrilateral shapes and ask students to identify the shapes.

Entry Behavior

Students are familiar with basic geometric shapes, including squares and rectangles, which are foundational concepts for understanding quadrilaterals.

Learning Resources and Materials

• Rulers
• Compass
• Protractors
• Set squares
• Visual aids of quadrilaterals

Building Background/Connection to Prior Knowledge

Students have previously studied lines and angles, which will assist in understanding the properties and constructions of quadrilaterals.

Embedded Core Skills

• Observation and spatial reasoning
• Geometric construction
• Classification and differentiation

Learning Materials

• Lagos State Scheme of Work for Technical Drawing
• Diagrams illustrating different quadrilaterals and their properties

Reference

• Lagos State Scheme of Work
• “Technical Drawing and Engineering Graphics” by A. Bankole

Instructional Materials

• Visual aids showing various types of quadrilaterals
• Drawing instruments for constructing quadrilaterals

Content Outline

1. Types of Quadrilaterals:
   • Rectangle, square, parallelogram, rhombus, trapezium.
2. Properties of Quadrilaterals:
   • Opposite sides, angles, diagonals, symmetry.
3. Construction of Quadrilaterals:
   • Steps to construct quadrilaterals with specific measurements.
4. Application in Real Life:
   • Identification of quadrilateral shapes in everyday objects.

Fill-in-the-Blank Questions

1. A quadrilateral with four right angles is called a ______ (a. square, b. trapezium, c. parallelogram, d. rhombus).
2. In a parallelogram, opposite sides are ______ (a. equal, b. unequal, c. different, d. none of the above).
3. A square is a type of ______ with all sides equal and all angles 90 degrees (a. rectangle, b. trapezium, c. parallelogram, d. quadrilateral).
4. The diagonals of a ______ bisect each other at right angles (a. rhombus, b. rectangle, c. trapezium, d. triangle).
5. The opposite angles of a parallelogram are ______ (a. equal, b. different, c. right angles, d. obtuse).
6. A ______ has only one pair of parallel sides (a. trapezium, b. rhombus, c. parallelogram, d. square).
7. ______ is a quadrilateral with all sides equal, but not necessarily right angles (a. rhombus, b. rectangle, c. trapezium, d. triangle).
8. The ______ is a quadrilateral where opposite sides are equal and parallel (a. parallelogram, b. square, c. trapezium, d. rhombus).
9. In a square, both pairs of opposite sides are ______ and ______ (a. equal, parallel, b. unequal, perpendicular).
10. The area of a rectangle is found by multiplying ______ by ______ (a. length, breadth, b. side, diagonal, c. base, height).

FAQ

1. What is a quadrilateral?
   • A four-sided polygon.
2. What are some examples of quadrilaterals?
   • Square, rectangle, parallelogram, rhombus, trapezium.
3. How does a rectangle differ from a square?
   • A square has all sides equal, while a rectangle has opposite sides equal.
4. What is unique about the diagonals of a rhombus?
   • They bisect each other at right angles.
5. Which quadrilateral has only one pair of parallel sides?
   • A trapezium.

Quadrilaterals

1. Describe Quadrilaterals:
   • Explanation: Quadrilaterals are four-sided polygons with specific properties based on side lengths and angles. Each type of quadrilateral has unique attributes, making them useful in various designs and structures.
   • Types of Quadrilaterals:
     • Square: All sides are equal, and all angles are 90°.
       • Example: Tiles and chessboards.
     • Rectangle: Opposite sides are equal, and all angles are 90°.
       • Example: Plane flat piece of paper , doors, and phone screens.
     • Parallelogram: Opposite sides are parallel and equal, and opposite angles are equal.
       • Example: Some desktop surfaces or tabletops.
     • Rhombus: All sides are equal, but angles are not necessarily 90°. Opposite angles are equal.
       • Example: Certain kite shapes and wall tiles.
     • Trapezoid (or Trapezium): Has one pair of parallel sides.
       • Example: The shape of some desk surfaces or trapezoidal wall tiles.
   • Why it’s Important: Understanding the properties of each type of quadrilateral enables students to identify and use them in technical drawings, construction, and design work where different shapes are needed for functionality or aesthetics.
2. Recognize Classroom Objects That Are Quadrilateral in Shape:
   • Explanation: Many everyday objects have quadrilateral shapes, making it easy for students to relate their understanding of geometry to real-life objects around them.
   • Examples of Quadrilateral Objects in the Classroom:
     • Whiteboard or Chalkboard: Usually rectangular.
     • Desktops: Often rectangular or square in shape.
     • Textbooks and Notebooks: Rectangular in shape, making them easy to stack and handle.
     • Windows: Typically rectangular or square, allowing for even distribution of light.
     • Tiles on the Floor or Wall: Often square or rectangular.
   • Why it’s Important: Recognizing these shapes in their environment helps students connect geometric principles with practical uses, enhancing spatial awareness and reinforcing the concept of quadrilaterals in design and architecture.
3. Construct Various Types of Quadrilaterals:
   • Explanation: Constructing quadrilaterals requires drawing specific angles and side lengths, which is a fundamental skill in technical drawing and design. This process reinforces understanding of the properties of each shape.
   • Steps to Construct Basic Quadrilaterals:
     • Square:
       • Draw one side to a given length.
       • Use a set square or protractor to measure 90° and draw the adjacent sides to equal lengths.
       • Close the square by connecting the last point back to the starting point.
     • Rectangle:
       • Start with one side.
       • Measure 90° angles to form each side, ensuring opposite sides are equal in length.
     • Parallelogram:
       • Draw the first side.
       • Use a protractor to set the angles at both endpoints.
       • Draw the opposite side parallel to the first, ensuring they are equal in length.
     • Rhombus:
       • Start with one side.
       • Use a compass to draw arcs from each endpoint, creating the other sides equal in length and at the necessary angles.
     • Trapezoid:
       • Draw the parallel sides with one longer than the other.
       • Connect the two sides with the non-parallel sides to complete the shape.
   • Why it’s Important: Constructing quadrilaterals helps students understand and apply geometric properties in a hands-on way, enabling them to visualize and create accurate shapes in technical drawings.

Presentation Steps

Step 1: Revision of Previous Topic
The teacher will briefly review triangles and their construction, as students will use similar techniques when constructing quadrilaterals.

Step 2: Introduction of New Topic
The teacher will introduce the properties of quadrilaterals, using diagrams and visual aids to explain each type.

Step 3: Student Contributions and Corrections
Students will participate in identifying and drawing different quadrilaterals with guidance and corrections from the teacher.

Teacher’s Activities

• Describe the characteristics of various quadrilaterals.
• Demonstrate construction techniques for drawing specific types of quadrilaterals.
• Guide students in constructing quadrilaterals based on given measurements.

Learner’s Activities

• Identify classroom objects with quadrilateral shapes.
• Draw and label different types of quadrilaterals.
• Practice constructing quadrilaterals using specific measurements.

Assessment

• The teacher will assess students’ ability to identify and construct quadrilaterals.
• Observation of students’ understanding of the properties of each type of quadrilateral.

Evaluation Questions

1. Name two properties of a square.
2. How does a rhombus differ from a rectangle?
3. Describe a trapezium.
4. What are the properties of a parallelogram?
5. How would you construct a square with a given side length?

Conclusion

The teacher will summarize the types of quadrilaterals, their properties, and their applications in real-world objects and structures.