1. Whole Number Mental Add and Subtract
Subtracting on a Number Line (to 10) Slides 2-6
Subtracting on a Number Line (to 20) Slides 7-11
Teachers
Use these experiences with whole numbers in any order to suit student needs.
The experiences should be repeated many times across the year.
Where possible, coordinate your language (and student language) to the actions occurring onscreen.
Hints
To use the pointer pen option to write numbers as provided by students: Click Slide Show. Right click mouse. Select Pen.
To start at a specific slide: Click on Slide Show. Scroll to the Slide you want. Click From Current Slide.

2. 7 - 3 = 4 1 2 3 4 5 6 7 8 9 10
7 - 4 = 3
Say: Here is a number line that we can use to help us do the sum 7 take 3.
Say: Here is 7 (point to the 7).
Ask: What will we take-away from 7?
Click to show the arrow move to the 4.
Ask: What does 7 take 3 equal?
Click to show the answer of 4 in the sum.
Repeat for 7-4

3. 8 - 5 = 3 1 2 3 4 5 6 7 8 9 10
9 - 5 = 4
As for slide 2.

4. 6 - 2 = 4 1 2 3 4 5 6 7 8 9 10
5 - 1 = 4
As for slide 2.

5. 7 - 7 = 1 2 3 4 5 6 7 8 9 10 =
As for slide 2.

6. 8 - 6 = 2 1 2 3 4 5 6 7 8 9 10
7 - 2 = 5
As for slide 2.

7. = 12 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 = 11 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
As for slide 2.

8. = 9 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 = 9 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
As for slide 2.

9. = 8 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 = 4 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
As for slide 2.

10. = 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 = 5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
As for slide 2.

11. = 10 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 = 10 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
As for slide 2.