Addition and subtraction - Three-digit and one-digit numbers not crossing 10 - Worksheet

The worksheet focuses on the addition and subtraction of three-digit and one-digit numbers, specifically when the sum or difference does not cross the threshold of ten. The National Curriculum objective for this lesson is to enhance the students' ability to perform these operations without the need for exchanging. The resources provided for this lesson include differentiated worksheets, teaching slides, and Base 10 manipulatives. The key vocabulary terms such as 'add', 'subtract', 'digits', 'place value', and 'strategy' are central to the lesson, ensuring that students are familiar with the concepts and terminology involved in these mathematical operations.

The primary task for the children is to add or subtract ones from a three-digit number, with a focus on understanding which digits are affected by this operation. For example, in calculations such as 215 – 3 or 215 + 3, students are encouraged to concentrate on the ones column, simply performing 5 – 3 or 5 + 3, respectively. The emphasis is on mental arithmetic as the best strategy, although the column method may also be used. To deepen their understanding, students are prompted to answer key questions about the process, such as identifying which column to focus on and observing patterns in the calculations. Additionally, practical activities may involve using Base 10 equipment to build and represent the numbers, allowing for a more hands-on approach to learning these mathematical concepts.