# Jigsaw Numbers

If you think of a 2 piece jigsaw with a number on each piece, then Jigsaw Numbers are the total of the two numbers in the ‘finished picture’.

Jigsaw Numbers are special (10, 100, or 1000 for example). Explain the jigsaw analogy and ask children to complete the jigsaw, simple! For example, if 4 is one jigsaw piece, ask the child if they can tell us what would be on the missing piece if the total is 10. If we can *see* the maths it helps us to *understand* the maths.

## Jigsaw Numbers to 10

Ready for the challenge of Jigsaw numbers to 10? This is an oral activity to enjoy, have fun with it! Just ask your child to tell you the bottom number (when added to the top number equals 10), then refresh the screen. In this example, the correct answer is 6! How fast can you go?

Simply refresh your screen (hit the F5 button) to change the number!

5

?

## Jigsaw Numbers to 100

Ready for the challenge of Jigsaw numbers to 100? This time, the bottom number added to the top number on the right equals 10. The bottom number added to the top number on the left equals 9. Two simple sums, which give you the jigsaw number to 100! In this example 2+8= 10 and 3+6= 9 so the answer is 68! Amazing! you just worked out 100 – 32 = 68 in seconds!

The target is still to find the missing jigsaw numbers quickly. Focus on the 2 simple sums, they always give you the right Jigsaw Number to 100!

Simply refresh your screen (hit the F5 button) to change the numbers!

4 5

? ?

When you can answer both simple sums quickly, and you want to increase the challenge further, try reframing the questions;

- just ask the subtraction question (100 – 32 = ?) or,
- ask a missing number box questions (32 + = 100), or
- placing the questions into the context of money, or other units of measure (£1 – 32p = ?).

*Each of these questions uses 32 (from the first example provided above).*