1. Decimals and Fractions Add or subtract decimals
Objectives
Day 1
Add/subtract multiples of 0.01 to/from numbers with two decimal places, crossing multiples of 0.1 and 1.
Day 2
Add 2 or 3 amounts of money using column addition.
Use rounding to check answers.
Day 3
Add 2 or 3 numbers with two decimal places in a measures context, e.g. metres. Use rounding to check answers.
Before teaching, be aware that:
On Day 1 children will need mini-whiteboards and pens.
Year 6

2. Decimals and Fractions Add or subtract decimals
Starters
Day 1 Count on in steps of 0.01 and 0.1 (pre-requisite skills)
Suggested for Day 2 Double numbers with 1 decimal place (simmering skills)
or Halve numbers with 1 decimal place (simmering skills)
Day 3 Round numbers with 2d.p. to the nearest 1 and 0.1 (pre-requisite skills)
Choose starters that suit your class by dragging and dropping the relevant slide or slides below to the start of the teaching for each day.
Year 6

3. Decimals and Fractions
Add or subtract decimals
Starter Count on in steps of 0.01 and 0.1
Pre-requisite skills – to use this starter, drag this slide to the start of Day 1
Count round the class in steps of 0.01 from 2.85 to at least 3.05 and back. Repeat, counting in steps of 0.1 from 7.35 to 8.35 and back.
Year 6

4. Decimals and Fractions
Add or subtract decimals
Starter Double numbers with 1 decimal place
Simmering skills – to use this starter, drag this slide to the start of Day 2
Play ‘In The Box’ at choosing ‘doubles & halves’, then U.t from the doubles column (remind chn that we call this ones and tenths, rather than units and tenths). Children write double of each number on their whiteboards. Click each box to open it so they can check their answers.
Year 6

5. Decimals and Fractions
Add or subtract decimals
Starter Halve numbers with 1 decimal place
Simmering skills – to use this starter, drag this slide to the start of Day 2
Show children the bar model diagrams. Explain that each of the two lower bars are the same size, i.e. half of the top number. Children copy and complete each bar model. Agree the answers together, then challenge children to draw three of their own bar models showing halves.
Year 6

6. Decimals and Fractions
Add or subtract decimals
Starter Round numbers with 2d.p. to the nearest 1 and 0.1
Pre-requisite skills– to use this starter, drag this slide to the start of Day 3
Play ‘Dartboard Rounding’ at Choose TU.t(h) – nearest 1. Choose either to reveal the answers in response to children saying the number to the nearest whole or input all the answers and then check whether they are correct.
Year 6

7. Decimals and Fractions Add or subtract decimals
Objectives
Day 1
Add/subtract multiples of 0.01 to/from numbers with two decimal places, crossing multiples of 0.1 and 1.
Year 6

8. Count in steps of 0.01 from 2.45 to 2.55.
Day 1: Add/subtract multiples of 0.01 to/from numbers with two decimal places, crossing multiples of 0.1 and 1.
Count in steps of 0.01 from 2.45 to 2.55.
2.52 – 0.03 Count back from 2.52 on the counting stick to find the answer.
We can use place value and number facts to bridge 2.5:
2.45
2.46
2.47
2.48
2.49
2.5
2.51
2.52
2.53
2.54
2.55
2.49
2.5
2.52
0.01
0.02
2.52 – 0.02 = 2.5 using place value
Year 6

9. We can also use place value and number facts to bridge 2.5:
Day 1: Add/subtract multiples of 0.01 to/from numbers with two decimal places, crossing multiples of 0.1 and 1.
We can count on from 2.47 on the counting stick to find the answer.
We can also use place value and number facts to bridge 2.5:
= 2.5 using number facts
= 2.54 using place value
2.47
2.5
2.54
0.03
0.04
Year 6

10. Count back from 2.05 on the counting stick.
Day 1: Add/subtract multiples of 0.01 to/from numbers with two decimal places, crossing multiples of 0.1 and 1.
Count back from 2.05 on the counting stick.
1.95
1.96
1.97
1.98
1.99 2
2.01
2.02
2.03
2.04
2.05
Now calculate 2.02 – 0.05
2.97 2
2.02
- 0.03
- 0.02
Today would be a great day to use a problem-solving investigation – The Size and Distance of the Planets’ from UC Berkeley – as the group activity, which you can find in this unit’s IN-DEPTH INVESTIGATION box on Hamilton’s website.
Alternatively, children can now go on to do differentiated GROUP ACTIVITIES. You can find Hamilton’s group activities in this unit’s TEACHING AND GROUP ACTIVITIES download.
WT: Game to add and subtract multiples of 0.01 crossing through multiples of 1 and 0.1 using a number line.
ARE/GD: Repeatedly add 0.06, then subtract Challenge to repeatedly add multiples of 0.01 to end on a given number.
Draw an empty number line jotting bridging 2.
Year 6

11. The Practice Sheet on this slide is suitable for most children.
Differentiated PRACTICE WORKSHEETS are available on Hamilton’s website in this unit’s PROCEDURAL FLUENCY box.
WT: Add and subtract multiples of 0.01, crossing through multiples of 1 and 0.1 using a number line.
ARE/GD: Add and subtract multiples of 0.01, crossing through multiples of 1 and 0.1 including word problems.
Year 6

12. Decimals and Fractions Add or subtract decimals
Objectives
Day 2
Add 2 or 3 amounts of money using column addition.
Use rounding to check answers.
Year 6

13. Remember to leave a blank row above the answer line.
Day 2: Add 2 or 3 amounts of money using column addition; Use rounding to check answers.
Three DVDs cost £10.49, £14.79 and £12.25.
Round to the nearest pound in order to give an estimate of the total cost.
Now let’s find the exact cost using compact column addition.
Add the £1s
Add the 10ps
Add the £10s
Add the 1ps £ £
+ £
Remember to leave a blank row above the answer line.
How does this compare with your estimate? 5 1 2 3
£ 3
7 .
Year 6

14. How does your answer compare with your estimate?
Day 2: Add 2 or 3 amounts of money using column addition; Use rounding to check answers.
Three DVDs costing £15.79, £8.69 and £12.45.
Round to the nearest pound in order to give an estimate of the total cost.
Now use compact column addition to find the exact total.
Is this right? £ £
+ £ £ £
+ £
Make sure that children leave a blank row above the answer line and align the decimal points correctly. Agree the answer as £36.93.
Children can now go on to do differentiated GROUP ACTIVITIES. You can find Hamilton’s group activities in this unit’s TEACHING AND GROUP ACTIVITIES download.
WT: Add two amounts of money, aligning digits correctly. Estimate totals first.
ARE: Add three amounts of money, aligning digits correctly. Estimate totals first.
GD: Write three amounts with a total within a given range.
How does your answer compare with your estimate?
Year 6

15. The Practice Sheet on this slide is suitable for most children.
Differentiated PRACTICE WORKSHEETS are available on Hamilton’s website in this unit’s PROCEDURAL FLUENCY box.
WT: Children start at question 1 adding mostly two amounts.
ARE: Children start at question 5 and do as many as they can.
GD: Children start at question 9 and add three amounts.
Year 6

16. Decimals and Fractions Add or subtract decimals
Objectives
Day 3
Add 2 or 3 numbers with two decimal places in a measures context, e.g. metres. Use rounding to check answers.
Year 6

17. How does this compare with your estimate?
Day 3: Add 2 or 3 numbers with two decimal places in a measures context, e.g. metres; Use rounding to check answers.
A group of scientists are investigating how far snails crawl in a day. Sally the snail crawled metres in the morning and 8.36 metres after lunch.
Round to the nearest metre in order to give an estimate of the total distance.
Now let’s find the exact total using compact column addition.
50cm + 30cm + 10cm = 90cm
7cm + 6cm = 13cm
Remember to leave a blank row above the answer line and align the decimal points. m m
How does this compare with your estimate? 1
3 m 1
8 . 9
Year 6

18. Day 3: Add 2 or 3 numbers with two decimal places in a measures context, e.g. metres; Use rounding to check answers.
Sidney Snail has crawled 12.34m, then 10.86m.
Round to the nearest metre in order to give an estimate of the total distance.
Now find the exact total using compact column addition.
30cm + 80cm + 10cm = 1m 20cm
This is very similar to adding amounts of money.
BUT we don’t need to write the last zero like we would for money, where we have to write £23.20, not £23.2.
We write this answer as 23.2m.
4cm + 6cm = 10cm m m
How does this compare with your estimate?
Carefully talk through adding 30cm, 80cm and to give 1m and 20cm. The ask children to finish off the addition.
Children can now go on to do differentiated GROUP ACTIVITIES. You can find Hamilton’s group activities in this unit’s TEACHING AND GROUP ACTIVITIES download.
WT/ARE: Shuffle given digit cards to make additions of distances in metres with 2 decimal places, round and find the total.
GD: Add and round three distances in metres (2 decimal places) crawled by snails. 1 1
0 m 2
3 . 2
Year 6

19. The Practice Sheet on this slide is suitable for most children.
Differentiated PRACTICE WORKSHEETS are available on Hamilton’s website in this unit’s PROCEDURAL FLUENCY box.
WT/ARE: Adding two distances.
GD: Adding three distances.
Year 6

20. Decimals and Fractions Add or subtract decimals
Well Done! You’ve completed this unit.
Objectives
Day 1
Add/subtract multiples of 0.01 to/from numbers with two decimal places, crossing multiples of 0.1 and 1.
Day 2
Add 2 or 3 amounts of money using column addition.
Use rounding to check answers.
Day 3
Add 2 or 3 numbers with two decimal places in a measures context, e.g. metres. Use rounding to check answers.
You can now use the Mastery: Reasoning and Problem-Solving questions to assess children’s success across this unit. Go to the next slide.
Year 6

21. Decimals and Fractions Unit 1 Problem solving and reasoning questions
Problem solving and reasoning questions   
Jo counts from a number to 4.5 in eleven steps of What was her starting number?
 Write the next 4 numbers in each sequence.
__ __ __ __
__ __ __ __
__ __ __ __
   
Write the missing numbers.
= [__]
[__] = 3.5
[__] = 4.76
Jim runs kilometres and Ann runs kilometres to meet him. How far have they run in total?
Year 6