Number bonds

The pairs that make 10, 20 and 100. They are the most useful facts a child learns before the times tables, because almost every mental method later leans on them.

to 10

The five pairs that make 10.

to 20

Built from the bonds to 10.

to 100

Bridge to the next ten, then to 100.

Why they come first

A child who instantly knows that 6 and 4 make 10 can add 26 + 4, subtract 10 − 6, and later bridge through ten to work out 8 + 5. A child who has to count for each one is doing three times the work every time. Bonds are worth over-learning.