Teachers' Guidebook for Primary Mathematics

Drawing a perpendicular to a straight line
from a point not on it

I. Opening

Letting pupils recall the place where they are standing now. (Starting line of this session)

T : Let us recall what we learned in the last lesson.
P's : (Answers)
T : In the last lesson, we learned the way to draw a perpendicular to a straight line from a given point on it.
Announcing what should be studied in this lesson. (Goal of this session)

T : Today, you will learn how to draw a perpendicular to a straight line from a given point not on it.

II. Developing

What you should do is to draw a perpendicular to this straight line from this point.
You are allowed to use a set-square.

P's	:	(Practicing to find a solution.)
T	:	You seem to have found some solutions. Please show your solutions.
P's	:	(Demonstrating their solutions.)
T	:	Can you tell me the reason why this straight line is perpendicular to the given straight line.
P's	:	(Discussing and expressing opinions.)
T	:	Well you found a solution. Let us confirm the solution once again.

III. Closing

In this lesson, we have learned a way to draw a perpendicular to a straight line from a given point not on it.

T	:	Let us recall what we learned in the last lesson.
P's	:	(Answers)
T	:	In the last lesson, we learned the way to draw a perpendicular to a straight line from a given point on it.