Introduction to Triangles
Grade 4/5
Lesson Study #1
N. Bekanovic, S. Jordan, N. Moore, A. Prosdocimo
What am I?
I can be big or small.
You can find me all around.
I am made up of three connected lines.
I have three vertices
I am a polygon.
Sailboat
How many triangles can you find?
Church
How many triangles can you find?
Tall Building
How many triangles can you find?
3D Shape
How many triangles can you find?
Quilt
How many triangles can you find?
PROCEDURE:
(1) You will be divided into partners.
(2) Each pair will be given a bag of pipe cleaners.
(3) Use these pipe cleaners to make different types of triangles.
(4) There are three colours of pipe cleaners. Each colour
represents a different length.
(5) You can use any combination of colours.
(6) Work with your partner to create many different triangles.
(7) You will be given THREE minutes to create these triangles.
(8) Display your triangles flat on the table.
DO NOT BEND, TWIST OR ATTACH ANY PIPE CLEANERS.
Time for an Observation Walk
(1) This is a chance to take a closer look at each
other’s creations.
(2) Use your eyes only.
(3) Make a mental note of the various triangles
you observe.
(4) Discussions will take place later in the lesson.
Let’s see your ideas!
Equilateral Triangle
A triangle that has all of its sides equal in length
Let’s see more of your ideas!
Isosceles Triangle
A triangle that has two sides equal in length
Let’s see more of your ideas!
Let’s see more of your ideas!
Scalene Triangle
A triangle that has no equal sides
Let’s look for these triangles
Can you find examples of equilateral triangles?
Can you find examples of isosceles triangles?
Can you find examples of scalene triangles?
Time to Communicate
What is the difference between an equilateral, scalene and
isosceles triangle?
Use words and pictures (with symbols) to explain your
answer.