Early Math · Grade K
Comparing Objects: Longer, Taller, Heavier
Quick answer
Things can be compared in more than one way: how long they are, how tall they are, and how heavy they are. To compare lengths, line two things up at one end and see which one sticks out past the other. To compare weights, hold one in each hand or use a balance. The words longer, shorter, taller, heavier and lighter describe what you find.
What you'll learn
- Name things about an object that can be measured, like length and weight
- Compare two objects directly by lining them up
- Use the words longer, shorter, taller, heavier and lighter
Things we can measure
Look at a pencil. What can we tell about it?
- It has a length: how long it is from end to end.
- It has a weight: how heavy it feels.
A tree has a height: how tall it is. A cup has a size: how much it holds.
Each of these is a thing we can measure. One object can have lots of them.
Compare two lengths
Which is longer, the pencil or the crayon?
Line them up side by side. Make one end match. Then look at the other end.
The pencil goes past the crayon. So the pencil is longer. The crayon is shorter.
Why the ends must line up
Say the crayon starts to the right of the pencil. Then its end might stick out more. It could look longer.
But that is a trick of where it starts. It did not grow. When both start at the same spot, the one that goes past is the longer one.
Compare two weights
Which is heavier, a book or a leaf?
Hold one in each hand. The book pulls down more. So the book is heavier, and the leaf is lighter.
A balance shows it too. The side with the heavier thing goes down.
Worked examples
Common mistakes
Practice problems
-
Name two things you can measure about a book.
Answer
Two of: its length, its height, its weight.
Full solution
A book is long from end to end, and it has a weight. Both can be measured.
-
Which is longer?
Which is longer? Answer
The fork
Full solution
They start at the same spot. The fork goes past the spoon.
-
A cat and a dog stand side by side. The dog is higher. Which is taller?
Answer
The dog
Full solution
Their feet are on the same floor, and the dog reaches higher.
-
Which is heavier, a sock or a shoe?
Answer
The shoe
Full solution
Hold them. The shoe pulls down more.
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On a balance, the side with the apple goes down. The other side has a grape. Which is heavier?
Answer
The apple
Full solution
The heavier side goes down.
-
Which is shorter?
Which is shorter? Answer
The key
Full solution
The key stops first, so it is shorter.
-
What word tells how tall a tree is: height or weight?
Answer
Height
Full solution
Tall is about height. Weight is about heavy.
-
Which is lighter, a feather or a brick?
Answer
The feather
Full solution
A feather hardly pulls down at all. A brick pulls down a lot.
-
Two straws are lined up at one end. They end at the same spot. What can you say?
Answer
They are the same length.
Full solution
Neither one goes past the other, so neither is longer.
-
Ali puts a long stick and a short stick side by side. The short one starts way out in front. He says it is longer. What went wrong?
Hint
Did the sticks start at the same spot?
Answer
He did not line up the ends.
Full solution
The short stick only looks longer because it starts out in front.
Line up one end of both sticks. Then the long stick goes past the short one.
Frequently asked questions
What can be measured about an object?
Its length or height, how heavy it is, and how much it holds. A pencil has a length and a weight.
How do I compare two lengths?
Line the two objects up at one end, side by side. The one that sticks out past the other at the far end is longer.
Why line up the ends?
If one object starts further along, it can look longer even when it is not. Starting together makes the comparison fair.
How do I compare weights?
Hold one object in each hand, or put them on a balance. The side that goes down holds the heavier object.
Is a bigger object always heavier?
No. A big beach ball is lighter than a small rock. Size and weight are different things to compare.
Standards alignment
This lesson covers the following Common Core State Standards for Mathematics.
- CCSS.MATH.CONTENT.K.MD.A.1Measurement and DataDescribe measurable attributes of objects, such as length or weight. Describe several measurable attributes of a single object.
- CCSS.MATH.CONTENT.K.MD.A.2Measurement and DataDirectly compare two objects with a measurable attribute in common, to see which object has "more of"/"less of" the attribute, and describe the difference.