Chapter 4: Shadow Story (Togalu)

When light falls on a thing, it makes a flat picture behind it , a shadow. Today we will play with shadows and meet the flat shapes hidden in them!

What we'll do

• Make shadows with a torch and our hands.
• Meet the flat shapes: circle, square, rectangle, triangle.
• Count sides and corners of each shape.
• Find these shapes in things around us.

The big idea

When you hold a ball in front of a torch, its shadow on the wall is a circle. A circle is round , no corners, no straight sides.

If you hold a matchbox, its shadow can be a rectangle. A rectangle has 4 straight sides and 4 corners. Two sides are long, two are short.

A square also has 4 straight sides and 4 corners, but every side is the same length. A chapati press makes a square shadow.

A triangle has 3 straight sides and 3 corners. A samosa makes a triangle shadow!

Flat shapes are different from solid shapes. A solid shape (like a ball) we can hold. A flat shape (like its shadow) is what we draw on paper. Drawings, rangolis and posters are full of flat shapes.

Let's play!

Torch and wall. In a dark room, shine a torch on a tumbler, a book and a triangle bhujiya pack. What shadow shape do you see for each?

Rangoli shapes. Make a small rangoli using only circles and triangles. Count how many of each you used.

Side and corner counting. Draw any 4 shapes. Under each shape write how many sides and how many corners it has.

A small story

Atif sat near a lamp one evening. He saw his cup make a circle shadow on the table. His book made a rectangle shadow. He laughed when his samosa plate showed three samosa-triangles on the wall. "Maths is hiding in my shadow!" he said.

Quick check

1. How many sides does a triangle have?
2. Which shape has 4 equal sides?
3. Name the flat shape with no corners.
4. A rectangle has how many corners?
5. Draw a shape with 3 sides and a shape with 4 sides.

What did we learn?

• Flat shapes are circle, square, rectangle and triangle.
• We can tell shapes apart by counting sides and corners.
• Shadows of solid things often show us flat shapes.