# what is a simple way to teach rounding and place value to third grades ?

Aug 27, 2014 3:34am

• Math
• K / 3
• Class Culture / Planning

2

• Aug 27, 2014 4:32pm

This video shows a fun way to do place value:

• Sep 15, 2014 7:55am

I like to teach rounding by beginning with having students generate a list of the multiples of 10 up to 100. List them vertically, leaving some space in between each value. Next, have the students generate some 2-digit numbers. Once everyone has a number, the objective is to locate the interval in which those values would be placed. For example, 16 would go in the interval between 10 and 20, and 31 would go in the interval between 30 and 40. Have students explain why they've placed a number within a given interval. For example, "31 has three groups of 10 and 1 unit. That's a little more than 30, because that has just three groups of 10 and no units. It's not as much as 40. That has 4 groups of 10. So 31 is more than 30 and less than 40."
Once students can easily place values within intervals, remove the support of having the intervals listed. Name a value and have students provide the multiples of 10 that would be found on either side. Use this skill to move to a horizontal number line. For example, if you say "31", they say " 30 and 40". From this point, you could lay out a long number line on the floor with painter's masking tape (leaves no residue) and use number cards to place the values. Then the big decision: Where do we put 31 on the number line? Is is closer to 30 or 40? How do you know? (It's helpful to have students find the midpoint (35) before trying to place 31. The concept of magnitude plays a major part in understanding rounding!