Doubling and Halving to 20: Building a Wall
Develop the concept of doubling and related halving for the wholes 12, 14, 16, 18.
Section One: Linear Representation
Section Two: Ten Frame Representation
Prior knowledge of five plus bonds, ten plus bonds and part-part-whole is required.
- double bond: a two-part bond, where both parts are the same
- one half of
- addition as “and”
- equals as “is”
- ten frame
- empty ten frame
A little easier
Represent doubles with fingers
Instruct students who experience difficulty to make the amount using their fingers in a subitised way.
- In pairs, each student makes 6 as five plus bond.
- Then one student places their hands below their partner’s, to make a ten plus bond, as illustrated below.
- Verbalise the double bond.
- Repeat for double 7, 8 and 9.
Click this link to read Teacher Notes for more information about using counters and fingers to support learning number bonds.
Activity 16, Doubling and Halving to 10: Bonds Building A Wall is the same activity but for wholes up to 10. This is significantly easier.
In the next activity students develop fluency with double bonds when they are presented in random order. Go to
Doubling and Halving to 20: Fluency Doubles, Filling A Wall