In other words, they never memorized their multiplication tables! Many times I have seen a student do poorly due to a weakness in basic math facts they should have learned in third grade.
Great, fun and free math worksheets should be able to present a mathematical problem in different ways. Math is after all nothing more than a numeric expression of some of life's simplest questions:
Subtract 1-, 2-, or 3-digit numbers from 3- and 4-digit number with/without renaming
They're also available for nearly all grade levels. There are printable middle school, high school, elementary school, and even pre-school worksheets.
math worksheets grade 3
math worksheets grade 1
math worksheets grade 5