KeyStage 2 Lower

Order and compare objects

Lesson

What is mass?

When we think about how heavy something is, we are thinking about its mass. We use units of measurement to describe the mass of objects, such as:

milligrams
grams, and
kilograms.

When we need to follow a recipe, kitchen scales help us weigh ingredients. We can stand on a set of scales to find our weight in kilograms.

Remember!

To put objects in order by mass, we need to make sure we are using the same unit of measurement, such as grams, for each object we are comparing.

We could weigh each object in a group to put them in order but we could also use balance scales. We can work out which object is heavier or lighter out of two objects, then compare it to another object.

In the video, we'll use the mass to compare objects, as well as balance scales.

Worked examples

question 1

We want to order these animals from $heaviest$ to $lightest$ .


Cockatoo	Sparrow	Pigeon

Which of these animals is the $heaviest$ ?
$Sparrow$
A
$Cockatoo$
B
Pigeon
C
Which of these animals is the second $heaviest$ ?
$Sparrow$
A
$Cockatoo$
B
Pigeon
C
Which of these animals is the $lightest$ ?
$Sparrow$
A
Pigeon
B
$Cockatoo$
C

Question 2

We want to order these animals according to their mass from $heaviest$ to $lightest$ .

Which of these animals is $heavier$ ? (The pigeon is on the left.)

$cockatoo$
A
$pigeon$
B
Which of these animals is $heavier$ ? (The sparrow is on the left.)

$sparrow$
A
$pigeon$
B
The animals weights in $decreasing$ order is:
$sparrow$ , $pigeon$ , $cockatoo$
A
$cockatoo$ , $pigeon$ , $sparrow$
B
$sparrow$ , $cockatoo$ , $pigeon$
C
$cockatoo$ , $sparrow$ , $pigeon$
D

Question 3

A $pelican$ weighs $12$12 kg, a $turkey$ weighs $35$35 kg, a $chicken$ weighs $3$3 kg and $an ostrich$ weighs $111$111 kg.

Choose the list that puts these $birds$ in order from lightest to heaviest.
$chicken$ , $turkey$ , $ostrich$ , $pelican$
A
$chicken$ , $pelican$ , $turkey$ , $ostrich$
B
$turkey$ , $pelican$ , $chicken$ , $ostrich$
C
$ostrich$ , $turkey$ , $pelican$ , $chicken$
D