Decimals - Adding Decimals (Crossing the Whole) - Presentation

In this engaging mathematics presentation, pupils in Year 6 delve into the world of decimals, specifically focusing on the concept of 'Adding Decimals (Crossing the Whole)'. The presentation is designed to help students comprehend how to add decimal numbers that result in a sum exceeding a whole number. This concept is akin to column addition with whole numbers, where sums in each column can exceed 9, prompting the need to carry over to the next column. Students are prompted to consider whether this principle can be applied to decimals. Initial activities guide them through using a place value grid to add decimals such as 0.435 + 0.652, encouraging them to explore the role of partitioning in simplifying the process.

Further activities build on this foundation, with exercises like adding 0.531 + 0.782 and using complements to 1 as a strategy for adding decimals, as demonstrated by Leanna's method. For example, to find the sum of 0.55 + 0.72, Leanna partitions the numbers to create whole numbers, which simplifies the addition process. The presentation also includes a practical activity where students use a six-sided dice to generate decimal numbers and add them together, aiming to approach a target sum without exceeding it. The session culminates with independent work, where students apply what they've learned by using both place value charts and column addition to solve decimal addition problems, deepening their understanding of the concept of 'Crossing the Whole' when adding decimals.