In order to approximate a total, or to help check the reasonableness of an answer, students need to be able to round to the nearest 10 or 100. Check out this lesson for a fun game that gives them practice rounding, adding, and subtracting.
Students that can write their own story problems, and create math situations that require thought and perseverance to solve, are students that understand. This engaging activity reviews all of the third grade concepts and creates a review packet as well!
Students need to understand what a rounded number represents, and how that representation may be for several numbers. As the students solve various situations in this lesson, they come to know that a rounded number represents 9 different values.