# How to Teach Number Bonds to 20!?

Discussion in 'Primary' started by davidjones123, Feb 3, 2012.

1. ### davidjones123New commenter

Hi all,

What is the best way to teach number bonds to 20? My Year 2 class is struggling MASSIVELY with this concept and I was wondering if anyone has any ideas or methods they use in their classroom?

Any ideas would be welcomed.

Cheers,

Dave

2. ### clawthorpegirlNew commenter

Don't know about the best way but these are some of the things I do with my Year 2 class.
Check if they know bonds to ten (if they don't then start there) then make explicit the links to bonds to 20 - if you know 1+9 = 10 what would you need to add to 1 to reach 20 etc. Show them the patterns by recording in order ie. 1=9 = 10 so 1+19=20 and 11+9=20, set this out on board going left to right.
Use lots of practical equipment to show them different ways to get 20 - multilink, Numicon, base 10, counters etc. Also use these to show relationship with bonds to 10. Give children time to use the equipment.
Do they understand that = means both sides have to balance, so if 20 on one side there has to be 20 on other side, practice finding the missing piece in bonds to 20.
Practice, practice, practice! My Maths lessons always start with mental/ oral work based on numberfacts - bonds, doubles, x tables. Tell children they are going to know these facts as quickly as they know their names. Play Bingo games, 1,2,3 Show Me with Number Fans, team them up and add some competition - how quickly can each team complete theirs...
Use number bonds in practical and problems solving activities to help children apply their knowledge.
Hope this helps.

3. ### gergil4New commenter

From my son's point of view:
1) a song - "1 and 9 are number bonds, 2 and 8 are friends, 6 and 4 and 7 and 3, 5 and 5 are twins."
2) a game called 'shut the box' which I now play with my Y3 using the numbers written on paper and adapted for numbers up to 20:
http://www.amazon.co.uk/BigJigs-Shut-the-Box/dp/B00009R62G

HTH

4. ### mystery10Occasional commenter

Well at our school number bonds to 20 are sent as a homework sometime in the first few weeks of year 1 with a note which says "number bonds to 20", so I've taught it twice at home so far.
It's making me think how badly I taught it now but it went like this:
you know that 4 + 6 = 10 (they had to know their number bonds to 10 before doing this)
so you know that 14 + 6 = 20 ----------- they proved this to themselves various different ways - abacus, fingers and toes, counters, smarties, number line, 100 square
then they did if for a few other pairs
you know that 3+7 = 10
so you know that 13 + 7 = 10
Then they worked out all the pairs
Then they learned it off by heart from little blank cards on to which I put the pairs on each side e.g. 17 on one side 3 on the other - the game was to say what was on the other side of the cards as fast as possible, turn the cards over and play the game again
Oh now I remember it was easier with the second child, I paid the first one to teach her on a long car journey with a reward at the end if she passed my test.
Don't know how you would do it with a whole class though. Set it for homework?

5. ### nooilpainting

Line up 20 children. 20 and nothing/zero/nought make 20!
One walks over to start new line. 19 and 1 etc etc.
Children could have numbers writ large on cards (double-sided? 18 /2? Diff colours? or diff colours for odd and even? - thinking as writing or vice versa).
Keep it 'concrete' until it's fixed.