The amount which a number is greater or smaller.

To partition one part from another (the subtrahend from the difference), or to decrease an amount by taking an amount away.

Calculate the difference in different contexts

Maths

In this unit pupils will add 3 addends. They will use a strategy such as finding 2 addends to total 10 or 2 numbers to bridge though 10.  In the future unit pupils will add and subtract 1s and 10s from 2 digit numbers. They will use number facts to add/subtract a single-digit number to/from a 2-digit number .They will use a part-part-whole model to represent addition and subtraction.

In the prior unit pupils revisited addition and subtraction within ten. They consolidated addition and subtraction strategies. In this unit pupils will add 3 addends. They will use a strategy such as finding 2 addends to total 10 or 2 numbers to bridge though 10.

Calculating within 20

When would we be best to use the ‘counting on’ strategy to find the difference?

If a book costs £4 and a toy car costs £12, how would we efficiently calculate the difference in price?

 A teddy costs £9 and a toy car costs £12, how would we calculate the difference in price?

It takes Sofia 4 minutes to walk to school.
It takes Jun 12 minutes to walk to school. 
How much longer does it take Jun to walk to school than Sofia? {{ }} minutes.

Jacob wants to buy a new pencil case that costs £12 and he has saved £9 so far. 
How much more money does Jacob need to save? £{{ }}

When playing a game, the difference between Izzy’s score and Lucas’ score is 3, Izzy scored 9 so how many points could Lucas have scored?

Which equation has been written to find the difference between 9 and 6?   

Here, we are finding the difference between…

How many have we ‘counted on’ on the number line?

Which pairs of numbers have the same difference of 5?

If I know the difference between 10 and 6 is 4, working backwards, I also know the difference between ___ and ___ is 4

This lesson will soon be taken down.

Calculate the difference in different contexts

Lesson outcome