NCERT Solutions Curiosity Chapter 6 .2 How to Group Materials? — Activity 6.2: Let us group
Book page 1036 Updated on2026-09-05
Q1.
Group the objects shown in Fig. 6.1 based on any common property, such as shape, colour, hardness, softness, shine, dullness or materials they are made up of.
Answer
Fig. 6.1 shows a gulel (catapult), a steel tumbler, a steel spoon, a cricket ball, a yellow plastic cup, notebooks, a pen, a wooden scale, a plastic scale, a paper punch, a glass bowl, a red pencil, a stone, a rubber ball, keys, a brass lock, a clay diya, glass marbles, a plastic sharpener, an ice-cream stick, a nail and a potted plant.
The same set can be grouped in many different ways — one grouping for each property you choose.
Property chosen
Group A
Group B
Material — metal or not
Steel tumbler, steel spoon, keys, brass lock, paper punch, nail
The big idea: there is no single “right” grouping. A grouping is right as long as every object in a group truly shares the one property you picked. Change the property and the groups change completely — the steel spoon sits with the lock when you sort by lustre, but with the pencil when you sort by shape.
Try This: Another property you can sort by is whether a thing floats or sinks in a bucket of water. Drop the ice-cream stick, the plastic cup, the nail and the stone into water.
Float or sink is one more property you can group by: a wooden stick floats, an iron nail of the same size sinks.
Q2.
Which property did you use to group the objects in Activity 6.2?
Answer
Write down the one property you actually used. For example:
Property used = the material the object is made of
Group 1 — metal: steel tumbler, spoon, keys, brass lock, nail
Group 2 — glass: bowl, marbles
Group 3 — wood: ice-cream stick, wooden scale, pencil
Group 4 — plastic: cup, sharpener, scale, pen body
Group 5 — clay: diya
If your friend used colour instead, his groups will be red things, yellow things, brown things — and both of you are correct.
Why we must name the property: a group is only meaningful when everyone knows the rule that was used to make it. “These five things go together” means nothing until you add “…because all five are metals”.
Q3.
Did your friends group objects based on similar properties?
Answer
Usually not — and that is the interesting part. In a class of forty children you will find several different groupings of the very same picture:
Some children sort by colour — all the red things together.
Some sort by shape — all the round things together.
Some sort by material — all the metal things together.
Some sort by use — all the writing things together.
Some sort by hardness or by shine.
Two friends who both chose “material” will get almost exactly the same groups. Two friends who chose different properties will get completely different groups — yet nobody is wrong.
Why it happens: every object has many properties at the same time. A cricket ball is red and round and hard and made of leather. Which group it lands in depends only on which of these you decide to look at.
Q4.
What did you learn from this activity?
Answer
Four clear lessons come out of Activity 6.2:
An object can be made from different materials. A tumbler may be of steel, glass, plastic or clay.
One material can be used to make more than one object. Glass gives us a bowl, marbles, a window pane and a bangle.
The method of arranging objects into groups is called classification. Objects are classified on the basis of a common property that they have.
The same set of objects can be classified in many ways — change the property, and you get a new set of groups.
Where you see it every day: in the kitchen all the katoris are stacked together; a grocer keeps spices in one corner and pulses and grains in another; a chemist arranges medicines shelf by shelf. Each of them is classifying — which is why they can find anything in seconds.