# Oh clever people.... Subtraction in year 2. What methods do you use to teach....

Discussion in 'Primary' started by whodbeateacher, Apr 28, 2011.

1. ### whodbeateacher

..... subtraction when bridging in year 2? I have a very able child who loves to partition everything to add / subtract. This is fine for simple stuff (75+22 or 75-22) but he comes unstuck when it involves bridging (75-28).
I've tried getting him to partition a bit (so 75-20 is 25 then take away 8 to get the answer) but he's really struggling.
How would you do this? Or shall I just persevere?

2. ### whodbeateacher

Oops. That obviously should read "75 - 20 is 55...." !!

Sorry.

3. ### slingshotsallyStar commenter

3 steps
75-28

A. round up 28 to 30
B. subtract 30 from 75

BPG

4. ### greta444New commenter

Use an empty number line. Take away 20, takes you to 55. Take away 8 and you're at 47.

5. ### pinkflipflop

Counting up to find the difference.
28 to 68 = 40
68 to 75 = 7
40 + 7 = 47

6. ### kimandju

I would introduce the empty number line, this will be useful when they use larger numbers as well and helps to reinforce place value.

7. ### Lara mfl 05Star commenter

As others have suggested I would use a numberline for counting on & back.