### Teaching and Group Activities for Understanding

**Day 1 Teaching**Use counting stick to count in 0.01s from 2.45 to 2.55 and back. Label 2.5 with a Post-it. Write 2.52 – 0.03. Count back from 2.52 to 2.49. Sketch a jotting to show how we ‘bridge’ 2.5. Repeat for 2.47 + 0.07. Mark the centre as 2, then count in 0.01s from 1.95 to 2.05 and back. Use the counting stick and a jotting to work out 2.02 – 0.05.

**Group Activities**

-- Game to add and subtract multiples of 0.01 crossing through multiples of 1 and 0.1 using a number line.

-- Repeatedly add 0.06, then subtract 0.07. Challenge to repeatedly add multiples of 0.01 to end on a given number.

**Day 2 Teaching**

Show 3 DVDs labelled £10.49, £14.79, £12.25. Estimate total cost by rounding. Model compact addition to find total cost. Remind children to leave a line below numbers being added so we can write extra digits. Finish and compare with estimate. Repeat for 3 other prices.

**Group Activities**

-- Add three amounts of money, aligning digits correctly. Estimate totals first.

-- Add two amounts of money, aligning digits correctly. Estimate totals first.

Write three amounts with a total within a given range.

**Day 3 Teaching**

Use the distance that snails crawl to generate decimal additions. Children round each distance to nearest metre to estimate the total. Model column addition, showing how to align decimal points.

**Group Activities**

Use the ‘Adapt Four of the Best’ in-depth problem-solving investigation below as today’s group activity.

Or, use these activities:

-- Add and round three distances in metres (2dp) crawled by snails.

-- Shuffle given digit cards to make additions of distances in metres with 2dp, round and find the total.