Addition and subtraction - Check answers - Planning

In Year 3's Autumn Addition and Subtraction curriculum, Lesson 7 introduces a critical mathematical skill: checking the accuracy of answers using inverse operations. To begin, the children recap their previous knowledge, ensuring they understand that using the inverse – the opposite operation – can help verify their calculations. For instance, if they have added numbers, they can subtract to check their result. The key terms for this lesson include 'Inverse', 'Place Value', 'Digit', 'Equals', 'Subtraction', 'Addition', 'Hundreds', 'Tens', and 'Ones'. The lesson starts with a group discussion about the concept of inverse operations, which should be familiar from Year 2. The teacher explicitly explains how to use inverse operations to confirm the correctness of answers in addition and subtraction problems.

During the class, students engage in a range of activities designed to reinforce their understanding of checking their work. They work through examples in pairs, using subtraction to verify addition results and vice versa. In a practical application, they use bar models to represent problems, such as Tia baking and selling cookies, to find the missing part and check answers with the inverse operation. Group work further develops their skills, where they create calculations from a set of number and operation cards, exploring different mathematical concepts and sentence stems to articulate their reasoning. The lesson concludes with independent practice through differentiated worksheets, and a reflection activity encourages students to consider what they have learned, the skills they used, and any challenges they faced. This ensures they understand the importance of verifying their answers and grasping the part-whole relationship in mathematics.