Addition and subtraction - Add and subtract 10s - Planning

In Year 2, students delve into the world of addition and subtraction with a focus on manipulating tens. This particular lesson aims to strengthen their understanding of place value and the effect of adding or subtracting multiples of ten to numbers within 100. Emphasis is placed on the tens digit and its significance in these calculations. For instance, when presented with the sum 34 + 20, students should recognise the result as 54, noting the tens digit increase. The lesson begins with an engaging activity where students count in tens both forwards and backwards from any starting point, using an interactive 100 square to visualise the pattern and reinforcing the concept that while the tens digit changes, the ones remain constant.

Students engage in hands-on learning by using Base 10 blocks and place value grids to build and manipulate numbers, such as starting with 23 and adding increments of 20, observing the changes in the tens place. They are encouraged to express their actions in both addition and subtraction calculations. Further activities involve fluency practice with Base 10, where students explore the connection between addition and subtraction, and how to represent these operations using various models like part-whole, bar models, or number lines. Group activities foster mathematical discussions, using sentence stems to articulate their reasoning. The lesson concludes with independent work on differentiated worksheets, tailored to support students working towards, at expected level, or at greater depth, ensuring a comprehensive understanding of the composition of numbers and the relationship between parts and wholes when counting in tens.