If you are looking for ideas for how to teach rounding, then you found the right place!
Rounding numbers is a math skill that can feel like it is easy to teach. Simply train you students how to circle a number, underline another, apply a rule, etc. Heck, I’ve even patted myself on the back for making up a catchy little ditty! This did help my 3rd graders ace the rounding questions on the state assessment. However, that did not mean they understood the concept. Nor did it mean they could apply it to real world situations. It’s not quite that simple.
It’s important to teach our students about what rounding actually means and why it’s important. Further, we need to support them in developing a deeper understanding of the number system. This post will share some ideas for how to teach rounding in October. In addition, it will suggest a math resource to help you do it. Learn more below!
How to Teach Rounding Using an Open Number Line
We round numbers when estimating is a “good enough” option. Rounded numbers are much easier to work with in our head. Since rounding “in real life” doesn’t involve a pencil and paper to circle and underline, it doesn’t make sense to teach it that way.
Have you met my friend The Open-Number Line? We weren’t really all that close at first. In fact, he kind of rubbed me the wrong way. I like rules and clear cut guidelines. He was far too wild and unpredictable for my taste. But then I took the time to get to know him better. And I learned we had addition in common. Then I had some students who really struggled with subtracting “big” numbers and he was there to lend a helping hand. From that point on, I was totally in love. We’ve been BFFs ever since. And I really encourage my students to make him a Bestie as well. He is great for many concepts: elapsed time, fractions – he’s got it covered!
Rounding is another area in which he excels. To show your students how to round, start with rounding to the nearest ten. Draw a number line and label each end with a consecutive multiple of ten (e.g. 20 and 30). Add a number in the middle (e.g. 24). Guide the students to see that 24 is closer to 20 than to 30. Do the same with 27 and guide them to see that it is closer to 30. Explain that when a number has a 5 in the ones place it is exactly in the middle of two 10s. In this case, we always “round up.” Once your students are comfortable working with tens, repeat the process using hundreds.
I decided to capitalize on the excitement that is the month of October and created a center and task cards to provide some additional practice for my 3rd graders. You are going to love this pumpkin-themed rounding math center!
This October rounding packet includes activities for rounding to the nearest 10, 100 and 1,000. This makes it great for differentiating to meet the varied needs os your students. It includes 7 different printables with open number lines to help students practice rounding on a number line. I suggest laminating the mats or inserting them into plastic page protectors and using dry erase markers for initial practice. You could also use a document camera to teach this as a whole class lesson.
It may be helpful for some friends to visualize the number line bent like a hill. This is why I included the hill clipart with the number line. I placed one of the pumpkins onto the number to show that the pumpkin would “roll” towards a multiple of 10, 100, or 1000.
The packet also includes 3 sets of task cards (24 cards each) and a recording sheet. The “task card” format is so much more exciting for students than a traditional worksheet. Check out my pumpkin-themed rounding activity to learn more!
