Rounding

Yesterday we began learning how to round numbers to the nearest ten. The children began to understand that sometimes you need to count with precise accuracy, but other times you can make an estimate. In situations that require only an estimate we round numbers. We looked at a number line so we could visibly see which multiples of 10 (the numbers you count when counting by 10) are closest to each number. I directly taught the children that numbers with 5 in the ones place always round up.

You can practice rounding to the nearest 10 at home! Ask your child to round 67 to the nearest 10. (67 rounds up to 70.) Or try 21. (21 rounds down to 20.)

This morning we practiced rounding to the nearest 100. When we round to the nearest hundred we look at the tens place to see which multiple of 100 is closest to the number. Just like rounding to the nearest 10 - numbers with 5 or higher in the tens place always round up. Numbers with 4,3,2,1 in the tens place always round down.

The trickiest part for some children is figuring out what the choices are. For example, if I am rounding 361 to the nearest hundred, I need to find the closest multiples of 100. Children need to know that 361 is between 300 and 400. Once they have determined this, they can see that 361 rounds to 400 because there is a 6 in the tens place.

Happy rounding! :o)