Estimate the Sum, Difference & Product Challenge

Estimate the sum, difference and product challenge is an online test to assess 4th or 5th grade student's math skills on finding the sum of two numbers, product of two numbers and difference between two numbers by rounding multi-digit whole numbers to the nearest 10, 100 and 1000 by estimation in pre-algebra or number and operations in base ten (NBT) of common core state standards (CCSS) for mathematics.