# Lesson overview:Applying mental calculation strategies to adding and subtracting decimals

- In this lesson, we will use a range of informal mental strategies to add and subtract decimal numbers.

## Core Content

- In this lesson, we will use a range of informal mental strategies to add and subtract decimal numbers.

## Calculating with whole numbers and decimals:

- Representing Decimals
- Multiplying and dividing decimals by 10,100,1000
- Deriving decimal addition and subtraction facts
- Adding decimals
- Subtracting decimals
- Applying mental calculation strategies to adding and subtracting decimals
- Solving problems with decimals using addition and subtraction
- Deriving Decimal Multiplication Facts
- Multiplying decimals by a whole number
- Multiplying decimals using a formal written method (short multiplication)
- Multiplying decimals using mental strategies
- Problem-solving with decimals in context
- Representing 2-digit by 2-digit multiplication
- Multiplying a 3-digit number by a 2-digit number
- Problem-solving with multiplication