Place Value, Rounding and Estimating

We are working on place value for the next six weeks. One of our EQs (essential questions) is about rounding. Teaching rounding to second graders is not the easiest concept. Here are some of the ways I have taught rounding:

 A friend taught the children that the number to be rounded is like Cinderella. The number to the right is the fairy godmother. She decides whether Cinderella gets a new "gown" (number) or not. Then, she vanishes and leaves a zero. 

I made up a little poem several years ago...
Stay the same
For zero to four,
Go on up
For five or more!

A first grade teacher draws a "hill" and puts the five at the top, toward the right as if it's getting ready to go down the hill to the right. 0, 1, 2, 3, and 4 are going up the left side...never making it up the hill. 6, 7, 8, and 9 are going down the right side of the hill. She puts the numbers on each side of the "hill" at the bottom.

Leah, my teamie, draws her "hill" to look like a rollercoaster. She draws the cars with numbers on them and puts people in the rollercoaster cars. So today, my students drew their own rollercoasters to show rounding. It's amazing how quickly you can see who has rounding and who doesn't! So, now we're on to reteaching!

A way we teach place value is to run colored copies (or let the students color their own) of hundreds from our Math series templates. The students use these and cut them into tens and ones to create pictures. Then, they count the hundreds, the tens, and the ones to add them together for the total from their pictures. We've done this as another way to practice as well as assess student understanding. You can use the Activboard to make pictures to show some ideas for students and teach them how to count the hundreds, tens, and ones. 

A student teacher also used Goldfish Colors (four colors: yellow, orange, green, & red) to practice place value. She gave out colored goldfish to each student and a place value chart to thousands. Each color represented a different value: ones, tens, hundreds, and thousands. She had a place value chart with construction paper goldfish hanging on yarn so she could turn it over and show the goldfish two ways. I did not put the fish on a place value chart. I just laminated the goldfish and put magnets on the back. I drew a place value chart on my white board and stuck the paper goldfish on it. That way I can use the fish four ways and have the students practice with each color being a different value. This may need to be modified to ones, tens, and/or hundreds for students struggling with place value.

We'll be doing this tomorrow so I'll add pictures soon! :)