Download Geometry Nomenclature: Triangles

© 2012 Montessori 123: Triangles 3-Part Simplified
Geometry Nomenclature: Triangles
Activity 1
Teach the parts of a triangle first. Students can make one out of
construction paper and use the cards to label the parts.
Activity 2
Teach the different types of triangles based on the number of
sides that are the same. Scalene triangles have 3 sides that are all
different, isosceles triangles have two sides that are the same and
equilateral triangles have three equal sides. Students can use a ruler to
measure. See if they can find examples in the environment.
Activity 3
Teach the different types of triangles based on angles. First show
how to use a measuring angle (right angle) to see if angles are the
same, smaller or larger. Acute angles are smaller and obtuse angles
are larger. Children enjoy using a measuring angle to find different
types of these angles in the environment. Children can then identify
triangles that have these angles. One example of each should be
recorded on paper.
Activity 4
After they have learned the terminology they can name triangles
such as obtuse-angled scalene triangle.
Activity 5
Play the detective game of triangles. Traditionally there are 54
triangles in three sizes and three colors. Start by writing “the triangle”
on paper. Add a clue such as “red”. There are still too many choices.
Add another clue such as “small”. The children will quickly see they
need all the clues: “The small red obtuse-angled scalene triangle”.
Once they understand the game they must find or draw the triangles
described.
© 2012 Montessori 123: Triangles 3-Part Simplified
base of the triangle
base of the triangle
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angle
angle
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© 2012 Montessori 123: Triangles 3-Part Simplified
sides of a triangle
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sides of a triangle
vertex
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vertex
© 2012 Montessori 123: Triangles 3-Part Simplified
area of a triangle
area of a triangle
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perimeter of a triangle
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perimeter of a triangle
© 2012 Montessori 123: Triangles 3-Part Simplified
right triangle
right triangle
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obtuse triangle
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obtuse triangle
© 2012 Montessori 123: Triangles 3-Part Simplified
acute triangle
acute triangle
equilateral triangle
equilateral triangle
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© 2012 Montessori 123
© 2012 Montessori 123: Triangles 3-Part Simplified
scalene triangle
scalene triangle
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isosceles triangle
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isosceles triangle