Addition and subtraction - Add and subtract three-digit and ​two-digit numbers not crossing 100 - Planning

The focus of this Year 3 lesson is on adding and subtracting three-digit and two-digit numbers, specifically when the two-digit numbers are multiples of 10 and do not result in crossing the hundred boundary. The lesson employs a variety of resources, including place value counters, mats, worksheets, and a presentation to visually and practically reinforce the concepts of addition and subtraction. Key vocabulary such as 'addition', 'subtract', 'hundreds', 'tens', 'ones', and 'multiple' are introduced to the children, who are expected to engage with 'fluent in four' questions as a warm-up. The lesson begins with a recap of previous learning, followed by practical activities where children use number stories and concrete resources to explore the effects of adding or subtracting multiples of 10 on a three-digit number, focusing on the changes in the tens column while the ones and hundreds remain constant.

The lesson continues with partner discussions and activities designed to develop fluency and understanding of the concepts. Children are encouraged to represent their calculations in different ways, such as through number stories and visual representations, to deepen their comprehension. They also compare mathematical statements and use concrete resources to verify their accuracy. The lesson includes reasoning activities that promote mathematical language and thinking, with stem sentences provided to support their explanations. Towards the end of the lesson, a 'Give me five' reflection exercise prompts children to consider what they have learned, the skills they have used, and what they found challenging. Differentiated activities are provided to cater to varying levels of ability, from working towards the expected level to achieving greater depth, with each level focusing on adding and subtracting multiples of 10 using visual aids, such as place value charts, and progressing towards mental calculations.