The Year 3 Subtract 1s Across a 10 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
multiple: A product of one number multiplied by another number. For example: multiples of 10 are the products of numbers multiplied by 10.
partitioning: The splitting of a number into different parts. For example: the number 547 can be partitioned into 500, 40 and 7.
number line: A horizontal or vertical line which has numbers placed at equal points. Number lines can be used to show either positive or negative numbers. Most number lines begin at 0.
number track: A representation of the order of numbers when counting. It can go forwards or backwards. It is similar to a number line, but numbers can go up or down in jumps of 1s, 2s, 3s etc.
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
• Working back to the previous multiple of 10 on a number line, with a part-whole model and a number bond.
Support
• Q1: Subtract across a 10 on a number line, with the previous multiple of 10 given.
• Q2: Complete part-whole models with the whole already shown.
• Q3: Solve two subtractions crossing a 10, with the first jump given.
Core
• Q1: Subtract across a 10 on a number line.
• Q2: Complete part-whole models to partition the ones.
• Q3: Solve four subtractions crossing a 10, with no model.
Stretch
• Q1: Subtract across a 10 on an empty number line, labelling it and marking both jumps.
• Q2: Complete part-whole models; previous multiple of 10 not given.
• Q3: Solve four missing number subtractions crossing a 10; the unknown changes position.
Reasoning and Problem Solving
Support
• Q1: judge a character’s two jumps back, with a number line given.
• Q2: judge an answer found by partitioning; with the part-whole model and the previous multiple of 10 given.
• Q3: find 3-digit numbers in a short range that cross a given multiple of 10; with the ones digit narrowed.
Core
• Q1: judge a character’s two jumps back to and from the previous multiple of 10.
• Q2: judge an answer found by partitioning the ones; part-whole model and answer given.
• Q3: find 3-digit numbers across a wider range that cross a multiple of 10.
Stretch
• Q1: judge two sets of jumps where the error is in the final subtraction; not the partition.
• Q2: judge an answer where the partition is correct, but the working may not be.
• Q3: find 3-digit numbers meeting a condition after subtracting.
Deeper Reasoning
The questions in this set focus on using clues to solve problems and matching equivalent calculations to deepen understanding in adding and subtracting numbers mentally, including: three-digit numbers and ones; three-digit numbers and tens and three-digit numbers and hundreds.
