Short Blocks

Maths Year 1/2 Spring Addition & Subtraction (B)

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

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Open Unit 1 and download the PowerPoint from 'Planning and Group Activities': a brilliant and ready-to-use maths lesson for your white board!

The PowerPoint incorporates step-by-step teaching, key questions, an in-depth mastery investigation, problem-solving and reasoning questions - in short, everything you need to get started.

All the other resources are there to support as-and-when required. Explore at your leisure - and remember that we are always here to answer your questions.

Unit 1 Addition (suggested as 5 days)

Objectives

Addition
Unit 1: ID# 12540

Y1: Add 1-digit numbers to 1-digit numbers then 2-digit numbers.
Y2: Add 2-digit numbers.

National Curriculum
Y1: Add/Sub (i) (ii) (iii)
Y2: Add/Sub (i) (ii) (iii)

Y1: Hamilton objectives
7. Know number bonds to 10, e.g. 5 + 5, 6 + 4, etc. Also know what is left if objects are taken from 10.
8. Begin to know pairs which make 5, 6, 7, 8, 9 and 20.
9. Begin to be aware of unit patterns.
11. Add small numbers by counting on.

Y2: Hamilton objectives
6. Use place value and number facts to solve problems.
10. Add a 2-digit number and tens; add two 2-digit numbers which total less than 100.

Planning and Activities

Day 1
Sort additions into 2 groups: those we prefer to calculate by counting on, and those where children would choose place value/number facts.
Further Teaching with Y1
Use the bead bar to show bridging 10 when adding 1-digit numbers.
Group Activities: T with Y1
Y1 -- Add two 1-digit numbers by bridging 10, using either a bead string or beaded line.
Y2 -- Sort and solve additions according to how they might best be solved (counting on, place value or number facts).

Day 2
Add 1--digit numbers of pennies, bridging 10p on a money line.
Further Teaching with Y2
Add 9 to 2-digit numbers by adding 10 then subtracting 1 on a 1 to 100 grid.
Group Activities: T with Y2
Y1 -- Use penny lines to help solve money additions, adding 1–6p or 1–10p.
Y2 -- Repeatedly add 9 on a 1 to 100 grid, starting at 19, and describe the pattern. Some children will work in pairs to add 10, then 9 to 2-digit numbers.

Day 3
Imagine the colours of beads when bridging 10 to find 8 + 3, for example. Discuss which additions bridge 10 and which don’t.
Further Teaching with Y2
Use place value cards then 10p and 1p coins to add pairs of 2-digit numbers (1s less than 10).
Group Activities: T with Y2
Y1 -- Use bead strings to add 5 and 6 to 6, 7, 8 and 9, discussing how the 5 and 6 are split each time. Record bridging 10 on a landmarked line.
Y2 -- Use 10p and 1p coins, or place value cards, to add 2-digit numbers.

Day 4
Use place value cards to add pairs of 2-digit numbers (1s greater than 10). Y1s use bridging to add the 1s.
Further Teaching with Y1
Use 1-digit + 1-digit facts to find 2-digit + 1-digit answers, such as using the answer to 4 + 3 to calculate 14 + 3, 24 + 3.
Group Activities: T with Y1
Use the in-depth problem-solving investigation ‘Domino additions’ as today’s group activity.
Or, use these activities:
Y1 – Refer to addition cards, or recall 1-digit + 1-digit addition facts; use these to find the answers to 2-digit + 1-digit calculations.
Y2 -- Use place value cards to add two 2-digit numbers, discuss if the 1s will make an extra 10 or not. Some children will sort additions into those with answers less/more than 80, because the 1s digits total more than 10.

Day 5
Calculate 5 + 4, 15 + 4, 25 + 4 … 95 + 4 on the 1–100 grid, discussing the pattern.
Further Teaching with Y2
Add 19 on a 1–100 grid by adding 20, then subtracting 1.
Group Activities:
Y1 -- Use dominoes to generate 2-digit plus 1-digit number additions in a pattern. Some children may answer addition number sentences, recognising and using known facts.
Y2 -- Add 19 on the 1–100 grid, by adding 20, then subtracting 1. Some children may add ‘nearly’ numbers using a calculator, look for patterns, predict answers

You Will Need

  • 20-bead & 100-bead bar; Class set of 100-bead strings
  • ‘0–20 beaded line’ (see resources)
  • ‘Sheet of 0–20 beaded lines’ (see resources)
  • Plastic Fly; Two hoops
  • ‘1–100 grid’ (see resources or use your own large grid)
  • ‘Using number facts and place value for addition’ sheet (see resources)
  • ‘0–100 beaded lines’ (see resources)
  • ‘Number cards’ (see resources)
  • ‘0–20p money lines’ (see resources)
  • Real 1p and 10p coins
  • 1–6 dice; 1–10 dice
  • ‘1–100 grids’ (see resources)
  • 10s and 1s place value cards
  • Interactive whiteboard 10p and 1p coins
  • ‘0–20 landmarked line’ (see resources)
  • ‘Addition cards’ sheets 1–4 (see resources)
  • 10–50 tens cards, 1–9 ones cards
  • 1–100 grid with multiples of 10 coloured red (see resources)
  • ‘Dominoes’ (actual or cut-out, see resources)
  • Calculators

Short Mental Workouts

Day 1
Pairs to 10

Day 2
Counting on and back in 10s

Day 3
More pairs to 10

Day 4
Fact families

Day 5
Doubles

Worksheets

Day 1
Y1: Use a beaded line to bridge 10.
Y2: Code a series of additions according to how they might best be solved (counting on, place value or number facts).

Day 2
Y1: Add two items using a penny line, bridging 10.
Y2: Add 10, then 9 to 2-digit numbers.

Day 3
Y1: Identify sums greater than 10, calculate using a beaded line.
Y2: Add 2-digit numbers (1s less than 10).

Day 4
Y1: Calculate additions using patterns and known number facts.
Y2: Add 2-digit numbers (1s greater than 10).

Day 5
Y1: Use facts to solve addition number sentences.
Y2: Add ‘nearly numbers’ by adding the multiple of 10 and then subtracting 1.
Use calculators to help look for patterns when adding 9, 19, 29 and 39.

Mastery: Reasoning and Problem-Solving

Y1

  • Write the number fact we use to solve:
    34 + 5 = __, 64 + 5 = __
    Write another sum that uses this fact.
  • Write three other number sentences I know if I am told that 5 + 6 = 11.
  • Choose two cards.
    [6] [5] [3] [4] [5] [4]
    Choose an efficient strategy to add them.
    Write the answer.
    Tell me what strategy you used.
    Choose three more and do it again.

Y2

  • Complete each number sentence:
    27 + ☐ = 46
    ☐ + 29 = 73
    ☐ – 19 = 56
  • Complete the patterns:
    17, 26, __,
    44, __, __.
    5, 34, 63, __, __.
  • Start with 21. Add 9, then add 19, then add 29. What is the answer?
    Subtract 9, then subtract 19, then subtract 29.
  • Start with 18 and do the same 6 calculations. Can you predict the answer before doing the last 3 calculations?
  • Here are the prices for 5 pencils:
    A 34p, B 29p, C 45p, D 52p, E 19p
    The total is 53p. Which 2 pencils did you buy?
    What is the most you can spend on 2 pencils?
    What is the least you can spend on 2 pencils?

In-depth Investigation: Domino additions
Y1 Children use dominoes to generate 2-digit number plus 1-digit number additions in a pattern.
Y2 Children use dominoes to generate pairs of numbers with a given total.

Extra Support

Y1: Mystery Sums
Finding how many more are needed to make 10.

Y2: Square Sums
Adding ‘friendly’ 2-digit numbers using partitioning (1s less than 10 and 10s less than 100)

Unit 2 Subtraction (suggested as 5 days)

Objectives

Subtraction
Unit 2: ID# 12556

Y1: Find a difference, subtract using facts.
Y2: Subtract using Frog or partitioning.

National Curriculum
Y1: Add/Sub (i) (ii) (iii); Meas (i)
Y2: Add/Sub (i) (ii) (iii)

Y1 Hamilton objectives
9. Begin to be aware of unit patterns.
17. Compare objects according to height, length, weight, capacity, using appropriate mathematical language.
18. Count uniform non-standard, then simple standard units to measure length/height, weight, capacity.

Y2 Hamilton objectives
6. Use place value and number facts to solve problems.
11. Count back in ones or tens or use number facts to take away, e.g. 27 – 3 = or 54 – 20 =.
12. Begin to count up to find a difference between two numbers with a small gap, e.g. 42 – 38.

Planning and Activities

Day 1
Hold up two pieces of ribbon. Which piece is longer? Measure each using cubes. Compare the two towers of cubes and agree the difference, in cubes, between the two pieces of ribbon. Show on a number line.
Further Teaching with Y2
Say you have 32p and spend 27p. Mark 32p on a 0–£1 penny line. We can count up to find a difference. Mark on 27p, and cross out pennies up to 27p, hop to 30p then to 32p: 3p + 2p is 5p left. Repeat for £23 – £16.
Group Activities: T with Y2
Y1 -- Measure hand spans with cubes and find the difference, or find the difference between towers of cubes.
Y2 -- Discover how much money is left by calculating differences using a penny line.

Day 2
Say that Frog helps us subtract by hopping up the number line to find a difference. Model how Frog hops from 37 to 45 on the bead bar to solve 45 – 37. Repeat on beaded lines.
Further Teaching with Y1
Make towers of 12 and 16 cubes. What is the same and what is different? They are the same colour but one is taller. Point to the 4 extra cubes. The difference between 12 and 16 is 4. Show on number line. Repeat with other pairs of towers.
Group Activities: T with Y1
Use the in-depth problem-solving investigation ‘Difference towers’ as today’s group activity.
Or, use these activities:
Y1 -- Find the difference between two towers of cubes.
Y2 -- Calculate the difference between two 2-digit numbers by counting up with Maths Frog, or play ‘snatch the match’: using the same strategy.

Day 3
In pairs, children make two towers of cubes, such that one tower is 2 cubes taller. They count how many cubes in each.
Further Teaching with Y2
Show 62p – 47p using a 0–£1 penny line. Cross out up to 47p. Draw 3 hops: 47 to 50, then 50 to 60 and 60 to 62. Repeat with 85 – 68. Repeat with 61 – 47 on a landmarked line.
Group Activities: T with Y2
Y1 -- Find as many pairs of towers that have a difference of 3,
using up to 21 cubes.
Y2 -- Solve subtractions of 2-digit numbers with answers greater than 10.

Day 4
Use the answer to 6 – 4 to answer 16 – 4, 26 – 4, 36 – 4, 46 – 4 show on 1–100 grid.
Further Teaching with Y2
Discuss whether Frog or partitioning is quicker/ easier to calculate 53 – 47 and 67 – 24.
Group Activities: T with Y2
Y1 -- Write a subtraction number sentence and pass it on to another child to answer. Some children may answer subtraction calculations on cards, recognising the number fact that will help.
Y2 -- Investigate an efficient method for subtracting (counting up or partitioning).

Day 5
Write 67– 24, 48 – 33 and 86 – 45. Y2s choose one to solve using partitioning. Y2s subtract 10s, Y1s subtract 1s. Y2s show one using Frog.
Further Teaching with Y1
Children identify a fact to calculate 18 – 4, 28 – 4 …‘anythingty’-eight subtract four. Write 27 – 3, 47 – 3 and 97 – 3 on the board. What fact can we use to calculate these?
Group Activities: T with Y1
Y1 -- Represent groups of subtractions on the 100-bead bar. Some children may identify subtraction facts to solve subtractions.
Y2 -- Sort subtractions according to children’s preferred strategy. Or make pairs of numbers, discuss how to subtract the smaller number from the larger number

You Will Need

  • ‘0–£1 penny line’ (see resources)
  • ‘0–£100 landmarked line’ (see resources)
  • ‘How much money is left?’ sheet (see resources)
  • 0–£1 landmarked lines (see resources)
  • ‘Finding change’ sheet (see resources)
  • Coins; Counters; Sticky notes; Ribbon; Cubes
  • Pen priced at 59p, other items with price labels of 55p, 57p, 58p, 56p
  • Maths Frog (toy)
  • 100-bead bar and tags
  • 0–100 beaded line (see resources)
  • 0–9 dice; 1-8 dice; 1–6 dice
  • ‘Use Frog to work out these subtractions’ sheets 1 to 3 (see resources)
  • 0–100 beaded and landmarked lines (see resources)
  • 0–100 landmarked line (see resources)
  • ‘2-digit number spinners’ sheets 1–3 (see resources)
  • 1–100 grid (see resources)
  • ‘Subtraction cards’ sheets 1, 2, 3 (see resources)
  • ‘Frog or partition’ sheet (see resources)
  • Place value cards; 1–9 digit cards
  • 100-bead bar
  • Two cards: ‘Partition’ and ‘Frog’

Short Mental Workouts

Day 1
Pairs to 10

Day 2
Subtraction facts

Day 3
Add to the next 10

Day 4
Place value

Day 5
Tell the time

Worksheets

Day 1
Y1: Find the difference in the length of the snakes shaded in blocks. Find differences in length between images of pencils.
Y2: Find how much money is left over when children buy a drink by finding the difference.

Day 2
Y1: Calculate differences in numbers of cubes between two towers.
Y2: Use Frog (counting up) to solve subtractions.

Day 3
Y1: Calculate more differences between towers; then investigate differences and answer questions.
Y2: Use number lines to find differences by counting up.

Day 4
Y1: Use patterns of 1s digits to help answer subtraction number sentences.
Y2: Rehearse Frog, then partitioning; then choose how to subtract.

Day 5
Y1: Write extra subtractions in ‘families’ of subtractions.
Y2: Choose a method to subtract. Explain reasoning.

Mastery: Reasoning and Problem-Solving

Y1

  • Write all the subtraction facts that begin 8 – ☐. You should be able to write nine or maybe even 10 different calculations!
  • Write a number fact where the difference is 38.
  • Write two subtractions which use this fact.

Y2

  • Find the change from 50p if I spend 38p, using a 0–50 penny line.
  • Draw Frog’s hops on a number line to show the difference between 43 and 36.
  • Draw Frog’s hops on a number line to show 65 – 58.
  • Tell Frog how many hops he will need to do for each of these subtractions:
    a) 45 – 38
    b) 62 – 45
    c) 71 – 65
    d) 34 – 18
    Now use Frog to help you solve each one.
    Were you right about the number of hops each time?
  • Explain which method you would choose to do each of these subtractions:
    47 – 24, 63 – 47, 74 – 64
  • Start with 99. Subtract 9, then subtract 19, then subtract 29.
  • Start with 88 and do the same 3 calculations (-9, -19, -29). Can you predict the answer?

In-depth Investigation: Difference towers
Children arrange four towers such that the difference between neighbouring towers is at least two.
or

Stop Me if You Can
Children create diagonal lines on a 1-100 grid by adding and subtracting 10 and 1, whilst trying to stop their partner doing the same.

Extra Support

Y1: Little Brother Big Brother
Using patterns and number bonds to work out related additions

Y2: Tall Towers
Finding a small difference