Short Blocks

Maths Year 5 Spring Decimals and Fractions (B)

Each unit has everything you need to teach a set of related skills and concepts.

Subtraction with decimals, e.g. money (suggested as 3 days)

Planning and Activities

Day 1 Teaching
Use javelin throws as a context to show how we can count up using Frog from 9.56m to 11.32m. Find other differences in throws measured in metres using Frog to count up. Ensure children are familiar with recording on an empty number line.
Group Activities
-- Explore differences between height and stride length in younger children.
-- Investigate pairs of lengths with given differences.

Day 2 Teaching
Display a table of distances, in which the lengths can include one or two decimal places, e.g. 5.3m and 4.56m. Use Frog (counting up) to subtract pairs of numbers with different numbers of decimal places. Ensure children are comfortable with the empty number line used in this way.
Group Activities
Use the ‘Decimal differences’ in-depth problem-solving investigation below as today’s group activity.
Or, use these activities:
-- Calculate height differences between 2m and 4m.
-- Investigate missing number subtractions.

Day 3 Teaching
Show children a table of prices from two bike shops. Use this to construct problems involving finding differences between amounts. Use counting up (Frog) to solve subtraction word problems.
Group Activities
-- Solve subtraction word problems, choosing an efficient strategy.
-- Rank subtractions in order of difficulty; choose a strategy to solve them.

You Will Need

  • Tape measures
  • Paper clips
  • Whiteboards and pens
  • Flipchart
  • Number cards 1–9
  • ‘Word problems’ sheet (see resources)

Mental/Oral Maths Starters

Day 1
Pairs with a total of 1 metre (pre-requisite skills)

Day 2
Subtracting numbers with one decimal place (pre-requisite skills)

Suggested for Day 3
Reading scales (mass) (simmering skills)
Scales reader from http://www.ictgames.com

Worksheets

Day 1
Use Frog to find the difference in tree heights.

Day 2
Find daily heights grown by a bamboo plant.
Find differences between numbers with different numbers of decimal places.

Day 3
Work in pairs to discuss, then solve, single-step and two-step word problems. These all involve subtraction, and some include another operation.

Mastery: Reasoning and Problem-Solving

  • Write the missing length in each bar model:
    Diagram 1
14.8m
7.89m

Diagram 2

5.25m
3.58m

Diagram 3

2.3m
1.09m
  • Sunil and Zoe were meeting. They cycled 25km between them.
    Zoe cycled 11.47km. How far did Sunil cycle?
  • Find the differences between:
    4.5 and 6.54
    3.4 and 5.43
    5.6 and 7.65
    What’s the same? What’s different?
  • If the change from £100 was as follows, how much was the total cost of the two pairs of trainers?
    Pair A: change = £34.61
    Pair B: change = £28.75

In-depth Investigation: Decimal Differences
Children subtract pairs of numbers with consecutive digits and different numbers of decimal places, and look for patterns in their answers.

Extra Support

Frog's Teeny Hops
Finding the difference between decimal numbers on either side of a whole number, e.g. 1.8 and 2.3.