# Lesson overview:Adding and subtracting multiples of 100 to/from 3-digit numbers

- In this lesson, we will use known number facts in order to mentally add and subtract multiples of 100 to and from 3-digit numbers. We will look at partitioning strategies and analyse place value to make mental addition and subtraction more efficient.

## Core Content

- In this lesson, we will use known number facts in order to mentally add and subtract multiples of 100 to and from 3-digit numbers. We will look at partitioning strategies and analyse place value to make mental addition and subtraction more efficient.

## Addition and subtraction:

- Adding and subtracting 1-digit numbers to/from 3-digit numbers
- Adding multiples of 10 to 3-digit numbers
- Subtracting multiples of 10 from 3-digit numbers
- Adding and subtracting multiples of 100 to/from 3-digit numbers
- Adding two 3-digit numbers (without regrouping)
- Subtracting two 3-digit numbers (without regrouping)
- Applying rounding for estimating (adding)
- Applying rounding for estimating (subtracting)
- Adding two 3-digit numbers (regrouping in one column)
- Adding two 3-digit numbers (regrouping in multiple columns)
- Subtracting 3-digit numbers (regrouping tens to ones)
- Subtracting 3-digit numbers (regrouping hundreds to tens)
- Subtracting 3-digit numbers (regrouping in multiple columns)
- Solving addition and subtraction word problems
- Solving word problems with unknown values