Place value - Rounding to the nearest 100 - Presentation

The concept of rounding to the nearest 100 is explored through a series of engaging activities designed to reinforce students' understanding of place value. Initially, students are prompted to identify which numbers are multiples of 100, providing a foundation for understanding how to round other numbers. The activities progress to ask students to determine which multiples of 100 a given set of numbers fall between. This step is crucial as it sets the stage for the rounding process, enabling students to visualise the position of numbers on a number line relative to the nearest hundreds.

Further exercises involve practical application, where students are tasked with rounding numbers to the nearest 100 on a number line, deciding whether each number is closer to the lower or upper hundred. For instance, they must determine if numbers like 337, 365, and 388 are nearer to 300 or 400. This activity is extended to include reasoning, where students must round numbers that have different digits in the tens and ones places, understanding why numbers ending in 50 to 99 round up, while those up to 49 round down. The presentation culminates in a discussion of the similarities and differences between rounding to the nearest 10 and 100, highlighting the significance of the tens column in this process and the reason behind the rounding rules based on the number of zeros in the rounded figure.