Mathematics: Class 1 — Chapter 2: What is Long? What is Round?

In this section, children learn to distinguish between objects based on their physical shapes: whether they are long or round.

• Long Objects: Objects that have length as their prominent dimension (e.g., a pencil box, a bat, a ruler, or legs).
• Round Objects: Objects that have a circular or curved shape (e.g., a ball, an orange, a coin, or a face).

Objects in our surroundings can be grouped by their similarity to standard shapes:

• Similar to a Ball (Sphere): Watermelon, football, orange.
• Similar to a Cap (Cone): Birthday cap, ice-cream cone, funnel, folded paper cone.
• Similar to a Glass (Cylinder): Water bottle, tumbler, candle.
• Similar to a Matchbox (Cuboid): Pencil box, book, cardboard box.

Through the story of a little lamb and her wise grandmother, children are introduced to how shapes behave on slopes.

• The grandmother helps the lamb escape from a wolf by putting her inside a dholak (a barrel-shaped drum).
• Because of its curved surface, the dholak rolls quickly down the inclined path, allowing the lamb to reach home safely.

Depending on their surfaces, different objects behave differently when pushed along a flat or inclined surface:

• Rolling: Objects with curved surfaces roll (e.g., a ball, a marble, an orange).
• Sliding: Objects with flat surfaces slide (e.g., a plastic box, a notebook, a flat eraser).
• Both Rolling and Sliding: Objects that have both flat and curved surfaces can both roll and slide depending on how they are placed (e.g., a coin, a water bottle, a carrom striker, a marker).

A summary of how common everyday objects behave on a slope:

• Football: Rolls
• Pencil Box: Slides
• Book: Slides
• Orange: Rolls
• Water Bottle: Rolls (on its side) and Slides (on its flat base)
• Glass/Tumbler: Rolls (on its side) and Slides (on its flat base)
• Spoon: Slides