Place value is the foundation for decimal notation. Year 5 students need to understand that in the number 45.237, each digit represents a different power of 10: the 4 is in the tens place, the 5 is in the ones place, the 2 is in the tenths place, and so on.
ACARA AC9M5N01 focuses on understanding the structure of the number system, including decimals to two decimal places. Scaffold this by using place value grids, base-10 blocks, and number lines.
