The Year 3 Add and Subtract 10s PowerPoint guides both teachers and children through the lesson, including use of the varied fluency, reasoning and problem solving, deeper reasoning and scaffolded resources. Key learning information about this step:
Key Vocabulary
Base 10: A physical resource which represents numbers. The small cubes represent ‘ones’; the rods represent ‘tens’ and are made up of 10 small cubes; the squares represent ‘hundreds’ and are made up of 10 rods; the large cubes represent ‘thousands’ and are made up of 10 squares.
place value chart: Used to identify the value of the digits that make up a number.
placeholder: 0 is used to hold a place in a number and maintain its place value.
Varied Fluency
Knowledge Organiser
• Designed to support all children via key information and examples.
For the purple sections of the four levels, copy and paste these from the first sheet of the varied fluency resource.
Scaffolded Examples
• Adding 10s using Base 10 and place value charts; subtracting 10s using Base 10 and place value charts.
Support
• Q1: Adding 10s on a place value chart, with related number facts.
• Q2: Adding and subtracting 10s in number sentences, shown with Base 10.
• Q3: A two-step number chain adding and subtracting 10s, shown with Base 10.
Core
• Q1: Adding 10s on a place value chart.
• Q2: Adding and subtracting 10s in number sentences.
• Q3: A three-step number chain.
Stretch
• Q1: Reading a number from a place value chart, then adding an amount given in words; completing blank number sentence.
• Q2: Missing number in three number sentences; variation in location of missing number box.
• Q3: A three-step number chain with word instructions, one of which is missing.
Reasoning and Problem Solving
Support
• Q1: Reasoning - judging whether a subtraction of 10s leaving 0 tens has been recorded correctly; a place value chart shows the starting number.
• Q2: Reasoning - deciding which of two children has added or subtracted 10s correctly; Base 10 shows the number.
• Q3: Problem Solving - designing two-step number chains that add only, or subtract only, multiples of 10; Base 10 shows the start.
Core
• Q1: Reasoning - judging whether a subtraction of 10s leaving 0 tens has been recorded correctly.
• Q2: Reasoning - deciding which of two children has added or subtracted 10s correctly.
• Q3: Problem Solving - designing two-step number chains that add or subtract multiples of 10.
Stretch
• Q1: Reasoning - judging a two-step calculation that adds and subtracts 10s.
• Q2: Reasoning - deciding which of two children has added or subtracted 10s correctly; numbers written in words.
• Q3: Problem Solving - designing three-step number chains that must include both addition and subtraction of 10s.
Deeper Reasoning
The questions in this set focus on finding different possible routes through a maze and exploring how shapes can be arranged on a grid to match the calculations to deepen understanding in adding and subtracting numbers mentally, including three-digit numbers and tens.
