ClassFlow
Class Flow: Estimating Sums and Differences
[Free Registration/Login Required] This flipchart is designed to teach third grade students the steps in estimating sums and differences. It also reviews rounding numbers to the nearest ten and hundred.
AAA Math
Aaa Math: Round to Nearest Ten Thousand
This site explains how to round whole numbers to the nearest ten thousand. Gives exercises and games to practice this skill.
AAA Math
Aaa Math: Addition Using Estimation
This site explains how to estimate sums by rounding whole numbers. Games and exercises are provided to practice the skill.
AAA Math
Aaa Math: Subtraction Using Estimation
This site explains how to estimate differences by rounding. Games and exercises are provided to practice the skill.
CK-12 Foundation
Ck 12: Arithmetic: Fraction Rounding to the Nearest Half
[Free Registration/Login may be required to access all resource tools.] Round given fractions to the nearest half.
AAA Math
Aaa Math: Estimating a Sum by Rounding
Use rounding to estimate the answer to an addition problem in this online game. As you play the game, running totals of correct and incorrect answers and your score are displayed.
CK-12 Foundation
Ck 12: Arithmetic: Fraction Ordering With Lowest Common Denominators
[Free Registration/Login may be required to access all resource tools.] Order fractions from least to greatest and greatest to least using lowest common denominators.
AAA Math
Aaa Math: Estimation Rounding
This site explains how to round whole numbers. Gives problems and games to practice this skill.