# Classification of Figures ( Number of Sides)

## Students` Learning Outcomes

• Classify figures according to the number of sides as quadrilaterals (rectangles, squares) and triangles.

### Information for Teachers

• A triangle has three sides and three vertices.
• • A quadrilateral has four sides and four vertices. • While teaching the lesson, also consult textbook where and when applicable.

### Material / Resources

Writing board, chalk/ marker, duster, cutouts of triangles, square and rectangle, meter ruler, textbook

### Introduction

• Show cutouts of triangle to the students and ask them to count its sides and vertices. • After taking their responses, show another types of triangles and ask to count its sides and vertices.
• Is there any difference in the number of sides and vertices of both triangles?
• Conclude to them that a three-sided shape is called triangle.
• A triangle has three sides and three vertices.
• Now show cutout of rectangle to the students and ask them to count, how many sides and vertices it has? • After taking their response, tell them that it has four sides and four vertices.
• Show them cutout of square and they will count the number of sides and vertices. • Ask the students, is there any difference in the number of sides and vertices of rectangle and square.

### Development

Activity 1

• Draw three points on the board and ask the students to copy on their notebooks and join these points to make a shape. • Ask the students about the name of shape (triangle) and the number of line segments.(3)
• Demonstrate to the students that a triangle has three sides AC, BC and AB and three vertices A,B and C. Activity 2

• Demonstrate the drawing of quadrilaterals to the students on the board.
• Mark four points on the board and join them to make a quadrilateral. Tell the students that the sides of quadrilateral can be of any length. • Check the result and ask them to identify squares and rectangles from these quadrilaterals.
• Ask from students, that rectangle and square are the examples of quadrilateral. Why?

Activity 3

• Demonstrate the concept of type of quadrilaterals as rectangle and square to the students.
• Draw square and rectangle on the board. • Ask from students, what is the difference between rectangle and square.
• After taking their response, explain to them that rectangle has equal opposite sides, whereas a square has four equal sides.
• Draw the following chart on the board; now call the students one by one to measure the lengths of the sides of the rectangle and square. Put their results in the table. ### Sum up / Conclusion

• A triangle has three sides and three vertices.
• A quadrilateral has four sides and four vertices. • Rectangle and square are example of quadrilaterals.

### Assessment

• What is the difference between these three figures?  