Using Addition and Subtraction 2

In this scheme of work for Year 4, children begin by recapping on how to check their addition and subtraction answers by using the inverse operation. Next they look at the language of addition and subtraction in more detail, and use this knowledge to solve a variety of word problems, all based around a fun sports day theme.

Children then use their understanding of addition and subtraction to solve different puzzles and problems, and develop their mental and verbal reasoning skills. The included printable resources are there to help you support and extend you class, along with the differentiated activity ideas, detailed lesson plan and lesson slides.

Inverse Operations

What does ‘the inverse’ mean? In this first lesson, children will recap on the inverse operation - they will know how to check the answers to addition number sentences with subtraction, and the answers to subtraction number sentences with addition. Children will understand how to identify if an answer is correct or incorrect based on the answer the inverse gives, and be encouraged to explain their reasoning for this. They will also learn the correct terms for the numbers that they are adding and subtracting in each number sentence.

The Language of Addition and Subtraction

In this lesson, children explore the varied language of addition and subtraction by identifying the words or phrases in a problem that indicate which operation is needed. In their independent activities, children will work out competitors’ scores by solving one- and two-step problems. Alternatively, children write their own word problems using the language of addition and subtraction for others to solve.

Word Problems

Children will apply their knowledge of the language of addition and subtraction to solve increasingly difficult two-step word problems. They will use their reasoning skills to discuss which information is important, what calculations are needed, and what order they need to be done in. Children will answer questions to compete in an ‘obstacle course’, or in the alternative activity, they will use their problem-solving skills to complete a number search puzzle.

Puzzles!

In this lesson, children use their knowledge of addition and subtraction to solve puzzles using the trial and improvement method. They develop their reasoning skills by explaining their thought processes and the steps they need to take in order to narrow down the possible answers and find the solution. In their independent activities, children will use this method to solve or even create their own puzzles based around sports day medal winners.

Reasoning Skills

In this final lesson, children will continue to develop their reasoning skills by solving missing number problems. They will identify various missing digits in both addition and subtraction column methods, and be encouraged to explain their thinking. In their independent activities, children will solve missing number problems, and identify whether or not they can be certain about their answers. Alternatively, children will generate their own column additions and subtractions based on given ‘rules’.