To work out an answer, often by adding or subtracting.

Not wasting time or effort. An efficient strategy is one we can carry out easily.

Use efficient addition strategies to calculate

Maths

Combine tens and ones within equations

Add two-digit numbers without crossing the tens boundary

Find the missing addend when adding two-digit numbers

Add 2-digit numbers when crossing the tens boundary

Solve problems involving the addition of two-digit numbers

Explain different strategies used to subtract

Solve equations involving the subtraction of two-digit numbers

Solve problems involving subtraction of two-digit numbers

Subtract two-digit numbers crossing the tens boundary

Find the missing part when subtracting two-digit numbers

Solve problems involving subtraction when bridging 10

Use efficient methods to solve subtraction equations

Solve problems involving addition and subtraction

Create addition and subtraction problems

In this unit pupils apply their knowledge of known facts and understanding of place value to add and subtract with 2-digit numbers both within and across the tens boundary. In the future unit pupils will add 3 addends, understanding they can be added in any order, bridging through 10.

In the prior unit pupils added and subtracted 1s and 10s from 2 digit numbers. They used number facts to add/subtract a single-digit number to/from a 2-digit number and used a part-part-whole model to represent addition and subtraction. In this unit pupils apply knowledge of known facts and understanding of place value to add and subtract with 2-digit numbers within and across the tens boundary.

In this unit pupils apply their knowledge of known facts and understanding of place value to add and subtract with 2-digit numbers both within and across the tens boundary.

Addition and subtraction of two 2-digit numbers

Izzy wants to solve the equation 2 + 4 + 50 = ? Which is the most efficient strategy to use?

Andeep estimates the cost of the items shown. Which of the following is most likely to be accurate?

For which of the following equation, would you use the bridge 10 strategy?

For which equations would you use the known facts strategy? Tick two.

Andeep’s items cost £35     Which of the following shows the cost of Izzy’s items?

Match to show which equations will have the same sum.

Look at the items in the shop. How much would a ball and a car cost? £{{ }}

Izzy buys an astronaut and a rocket. Which known fact would she use to help her calculate the cost?

Andeep spent £43 at the shop. Which two items did he buy?

Which known fact would you use to calculate the cost of a penguin and an astronaut?

Which known fact would you use to calculate the cost of a unicorn and a car?

Andeep uses the 'bridge 10' strategy to find the cost of two items. Which two items were they?

Use efficient addition strategies to calculate

Lesson outcome