### Teaching and Group Activities for Understanding

**Day 1 Teaching**

Show children a 1–100 grid. Remind me how Spider can help us to add. Point at 21. Model how Spider counts in 10s down the grid. Use Spider to help children find 10 more than any number. Record each calculation like this: 21 + 10 = 31. Then progress to 20 more.

**Group Activities**

-- Roll a dice to generate a number of 10s to add to a number. Add and record a number sentence.

-- Choose a 2-digit number, then +10, 20 and 30 to it.

-- Work out the missing number in an addition number sentence.

**Day 2 Teaching**

Write 53 + 11 = __ on the board. Point at 53 on the 1-100 number grid. Demonstrate what 50 + 10 is using Spider. Then use Fly to add 1 more. Record: 53 + 11 = 64. Repeat this to demonstrate how we use Spider and Fly to help us add 11 to a multiple of 10, e.g. 30, i.e. Fly moves down to the beginning of the next row. Ask children to collaborate to add 11 to 44 and to 38.**Group Activities**

-- Work out the new price for the stationery after a price increase of 11p.

-- Explore the 100 grid to add 11 to a range of numbers. Work backwards to find a starting number.