Make a colourful paper quilt completely out of triangles in this fun and engaging activity exploring geometry and shapes!
Materials
- Square piece of paper
- Pencil crayons
- Pencil
- Ruler
- Protractor
All About Triangles
Before you begin creating and cutting out the triangle shapes needed for your paper quilt, let’s learn about the different types of triangles!
Triangles can be classified based on their sides as well as their angles.
Equilateral
In an equilateral triangle, all the sides are equal.
Isosceles
In an isosceles triangle, only two of the three sides are equal.
Scalene
In a scalene triangle, none of the sides are equal.
Right Triangle
A right triangle has one right angle which is equal to 90 degrees.
Obtuse Triangle
An obtuse triangle has one obtuse angle which is greater than 90 degrees.
Acute Triangle
An acute triangle has all acute angles which means all the angles are less than 90 degrees.
Triangle Characteristics
What are the characteristics that make up a triangle? … A triangle must have three sides, three vertices, and three interior angles that add up to 180 degrees.
What are congruent shapes? …Two shapes are congruent if they are the same shape and the same size, and can be rotated, translated or flipped to fit on top of one another perfectly.
What is the relationship between sides and angles? …The longest side in a triangle will be opposite to the largest angle, and the shortest side will be opposite to the smallest angle. If any of the sides in a triangle are equal then the corresponding angles will be equal too.
How to Create the Paper Quilt
Step 1
Make sure you have a square piece of paper.
If you do not have a square piece of paper, take a regular 8.5×11 paper and fold one corner across to the opposite side so that the edges of the paper line up, fold it along the seam, then cut off the excess.
Unfold your triangle and you should now have a square!
Step 2
You will first draw your quilt design in pencil.
Your quilt must include at least one example of each type of triangle.
This includes: equilateral, isosceles, scalene, right, acute, and obtuse triangles.
Step 3
Use a ruler and protractor when constructing your triangles to ensure that you are making the right kind.
Step 4
Now, sketch your quilt design with pencil. Make sure you have each type of triangle before proceeding.
Tip: Use the corner of the paper to make the right triangles! Why might this be easier?
Step 5
Time to colour your quilt.
Colour each type of triangle the same colour.
For example, colour all the equilateral triangles blue. If a triangle has more than one classification (e.g. It is both acute and equilateral), then colour it half of each type.
Try this! See if you can find any congruent triangles in your quilt. If you do, draw a symbol in the middle of the triangles to show that they are congruent. Use a different symbol for each pair.
STEM Challenge
Which angle and side combinations are not possible?
Why?
Answer: Equilateral triangles can’t be right or obtuse triangles because since all the sides are the same, all the angles have to be the same too. The angles in a triangle need to always add up to 180 degrees. This means that the angles in an equilateral triangle will always be acute and 60 degrees.
