Learning Objectives
To investigate the angle sum of polygons.
What do the internal angles of a megagon sum to?
Resources
Starter
What is an angle? How do we measure an angle? What does this tell us?
Level 4
To investigate the angle in a triangle. What can we say about the angles in an equilateral triangle?
Ask students to cut out a triangle and then mark the three corners.
Now cut the corners off the triangle corners.
Now put the points together to find out what the angles in a triangle add up to.
To investigate and then remember the rules for calculating internal angles in polygons.
In words, can you state the rule for the internal angles of any polygon?
Ask students to draw a six-sided shape (but making sure it is not a concave shape - see the picture).
Now pick one corner and draw straight lines from this corner to each of the other corners.
What shapes does this form within the larger shape?
What does this tell us about angles in the larger shape?
Ask students to now investigate other polygons.
Draw an example of each shape (they do not need to cut them out) and follow the method above.
Ask students to make a poster showing their findings.
Use the internet to find the names of the different polygons.
Use this information to complete the table below.
