### Teaching and Group Activities for Understanding

**Day 1 Teaching**Display 26 and model how to draw a jotting to partition:

Double 26

/ \

40 12

40 + 12 = 52

Demonstrate how the same jotting will help us partition a number to halve it. Repeat with other numbers.**Group Activities**Use the ‘Doubling Forever’ in-depth problem-solving investigation below as today’s group activity.

Or, use these activities:

**Find double and half of odd and even 2-digit numbers.**

**Day 2 Teaching**Write 226 and draw a partitioning jotting to show children how to double this number. The same process can be modelled for halving. Demonstrate how the jotting is crucial (we use it to partition the numbers).

**Group Activities**

Use doubling to check halving answers.

Double and halve 3-digit numbers.