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Learning by Doing

Objective: To understand the concept of symmetry.
Materials Required: Paper sheets (coloured or white), pencil, scissors, scale.
Procedure:
• Take two sheets, in which one is simply folded in half and the other paper in half twice,
to make a square. See in figures (i)(a) and (ii)(a).

Fig (i)(a) Fig (ii)(a)
• Draw two different designs on both sheets as shown below.

Fig (i)(b) Fig (ii)(b)
• Cut out the design from both sheets and make sure that the fold line is not cut away.

• Unfold the paper to get both the shapes that has lines of symmetry.

• Thus, the resulting shape in fig (i)(c), will have one line of symmetry and the resulting
shape in fig. (ii)(c) will have two lines of symmetry.

Fig (i)(c) Fig (ii)(c)
Observation:
• By unfolding each of the shapes in half and half twice respectively, we get the cutout
figures on both sides of the lines are same. This means there are one and two lines of
symmetry, respectively.
• Now, take another square sheet and fold in half twice and then fold on the diagonal to
make a triangle. Then, draw a design and cut out the shape. How many lines of symmetry
will you get?
• What design will you get after the paper is opened up?

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