This week we are going to be learning about number bonds to 20.
This is where 2 numbers add together to equal 20.
Today you will need 20 objects to use.
With these objects can you split them into 2 groups to see how many different ways you can make 20?
This number bond is 9 and 11 which makes 20.
So the number sentence is 9 + 11 = 20
What other number bonds to 20 can you make?
Can you write the number sentences to match too?
Today we are going to think about counting on to help us solve some maths problems.
"If I have 12, how many more do I need to make 20?"
So, we know we already have 12, so we don't need to start from 1 to count. We can count on from 12.
Use your fingers to help you count on. Put 12 in your head and put 1 finger up each time you say a number until you get to 20.
Now count how many fingers you are holding up.
We have 8 fingers up, so we need 8 more to make 20 from 12.
12 + 8 = 20.
Now try again with the following:
- "If I have 16, how many more do I need to make 20?"
- "If I have 7, how many more do I need to make 20?"
- "If I have 10, how many more do I need to make 20?"
- "If I have 18, how many more do I need to make 20?"
Now can you find who can make the number bond to 20 on the PowerPoint below:
The Space Master or the Space Villain?
Today we are going to be solving the missing number in a number sentence.
Remember about the skill we learnt yesterday to count on to help you.
Go through the PowerPoint below and use your fingers to help you work out the missing number in the number sentence.
For example if it says 17 + ____ = 20.
Put 17 in your head and count on until you get to 20!
Click on the picture below to help the rockets avoid crashing into the planets by working out the number bonds quickly!
Now we are familiar with our number bonds to 20, let's play some games!
Click on the picture below to play 'hit the button' and click 'up to 20'
Can you go onto purple mash to play another number bond to 20 game.