This is a large group game to teach the importance of looking at the "neighbor" when rounding.  
Rounding Game 
In this program student estimate the sums and difference of three digit numbers by rounding.  
Estimate by Rounding 
This program gives students a chance to practice rounding numbers. It goes from numbers in the hundreds to numbers in the millions with decimals.
This is an original poem written to help the students remember the steps to round a number.  
Rounding Rap 

Click here to print Rounding Rap Words.  
Click here to see game directions
Numberline Estimating
Users need to find points on a numberline between tens and hundreds.
In this program student use the concept of riding a bike over a hill to learn how to round.
Rounding Hills