Resources:
• masking tape
• table / whiteboard / flat surface covered if cannot be easily wiped
• whiteboard marker
• protractor
Lesson Description:
1. First watch this video with the pupil to see how we can use a protractor to measure angles.
2. Next tell the pupil that he has to use strips of masking tape to ‘draw’ lines on a flat surface, such as a table, whiteboard etc. It is important that the pupil understands that the tape has to be straight and goes across the table / whiteboard from one side to the other. The lines have to cross each other at least at one point.
3. Now you should have a surface full of angles. Ask the pupil to grab a whiteboard marker and protractor and start measuring as many angles as he / she could).
4. While doing so discuss how we can classify these angles. Are they acute, obtuse, right-angle?
5. You can also discuss how if for example you can find an adjacent angle to a known angle on a straight line without using a protractor, if the pupil knows that angles on a straight line add up to 180 degrees. Same goes for the total sum of angles in a triangle. If the pupil knows that they add up to 180 degrees and two angles are known than he / she can easily find the third one.