Common Core is all about getting your learners to open their minds and think about the why and how. This problem has them thinking about unknown numbers and their relationship with one another when we round and...

How accurate are robots? Groups draw lines by moving robots backwards and forwards by one rotation of the wheels. Using the appropriate formula, they determine the percent error in the length of the lines in relation to the calculated...

How much can a company round numbers without being misleading? Learners investigate the accuracy of claims made by a sports drink company. Teachers could easily modify the activity by bringing in their own beverage bottles, or by taking...

In this activity, students will round fractions and mixed numbers, and then use their rounding skills to estimate sums, differences, products, and quotients.

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.