The Year 2 Add Two 2-Digit Numbers (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
ones: Individual units that make up a whole number.
tens: A group of 10 ones together is the same as 1 ten.
exchanging: Exchanging can occur when completing calculations. It may also be known as ‘carrying’ or ‘borrowing’. In addition, an exchange happens when a place value column has a value of 10 or more.
total/altogether: Describes the new whole number that is created by adding parts together.
Varied Fluency
Knowledge Organiser
• Designed to support all children via key information and examples.
Scaffolded Examples
• Counting the tens and ones in Base 10; adding the ones and exchanging 10 ones for 1 ten; adding the tens to find the total.
Support
• Q1: Add two 2-digit numbers using Base 10; the ones to add are given.
• Q2: Find the whole in one part-whole model; add the ones first, then the tens.
• Q3: Solve an addition word problem with a bar model; add the ones first.
Core
• Q1: Add two 2-digit numbers using Base 10; complete the ones, tens and total.
• Q2: Find the whole in two part-whole models; the ones to add are given.
• Q3: Solve an addition word problem using a bar model with the parts given.
Stretch
• Q1: Add two 2-digit numbers using Base 10; complete the ones, tens and total.
• Q2: Find the whole in two part-whole models; the ones to add are given.
• Q3: Solve an addition word problem using a bar model with the parts given.
Reasoning and Problem Solving
Support
• Q1: Reasoning – judge a character’s addition; the ones make 11 or 12.
• Q2: Reasoning – complete one addition; check an exchange claim.
• Q3: Problem Solving – find three possible ones digits using an exchange clue; the tens digit is shown.
Core
• Q1: Reasoning – judge a character’s addition; the ones make 13.
• Q2: Reasoning – complete one addition; check an exchange claim.
• Q3: Problem Solving – find three possible pairs of ones digits using an exchange clue; the tens digits are shown.
Stretch
• Q1: Reasoning – judge a character’s addition from the answer and one fact.
• Q2: Reasoning – complete a part–whole model and addition; check an exchange claim.
• Q3: Problem Solving – find three possible 2-digit numbers using an exchange clue; explain each choice.
Deeper Reasoning
The question in this set focuses on finding a route by adding numbers greater than 10 while keeping the total below 100 to deepen understanding in adding and subtracting numbers using concrete objects and pictorial representations, including: a two-digit number and ones; a two-digit number and tens and two two-digit numbers.
