The Year 3 Subtract Two Numbers (across a 100) 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
place value chart: Used to identify the value of the digits that make up a number.
place value counters: A physical resource which represents numbers. They are usually in different colours and have different numbers written on them, to represent ‘ones’, ‘tens’, ‘hundreds’ etc.
exchange: When a digit is taken from one place value column and placed in another.
formal written method: This is also known as the column method for addition, subtraction and multiplication. For division, this may also be known as the bus stop method.
Varied Fluency
Knowledge Organiser
• Designed to support all children via key information and examples.
Scaffolded Examples
• Using place value counters and sentence stems to subtract two 3-digit numbers with an exchange.
Support
• Q1: Subtract two 3-digit numbers using place value counters; the exchange is given.
• Q2: Complete two column subtractions; the exchange is given; up to two exchanges.
• Q3: Compare two days in a table; the subtraction and the exchange are given.
Core
• Q1: Subtract two 3-digit numbers using place value counters; one exchange.
• Q2: Complete two column subtractions; up to two exchanges.
• Q3: Compare two days in a table; subtraction given.
Stretch
• Q1: Subtract two 3-digit numbers using place value counters; two exchanges.
• Q2: Place the digits in the grid and complete the subtractions; up to two exchanges.
• Q3: Compare two days in a table; set out the subtraction in the grid.
Reasoning and Problem Solving
Support
• Q1: Reasoning - judge whether a character has exchanged correctly; one exchange; place value charts provided.
• Q2: Reasoning - decide whether a stated missing digit in a column subtraction is correct; exchange given; one exchange.
• Q3: Problem Solving - make two subtractions from three digit cards; the number subtracted from is given.
Core
• Q1: Reasoning - judge whether a character has exchanged correctly; one exchange.
• Q2: Reasoning - decide whether a stated missing digit in a column subtraction is correct; one exchange.
• Q3: Problem Solving - make three subtractions from six digit cards, using each card once.
Stretch
• Q1: Reasoning - judge whether a character has exchanged correctly; two exchanges.
• Q2: Reasoning - decide whether a stated missing digit in a column subtraction is correct; two exchanges.
• Q3: Problem Solving - make three subtractions from six digit cards that also meet a condition on the answer.
Deeper Reasoning
The questions in this set focus on finding a path through a maze and using the clues to identify the missing digits to deepen understanding in subtracting numbers with up to three digits, using formal written methods of columnar subtraction.
