3rd Grade Addition Within 1,000 worksheets

About this worksheet

Adding within one thousand extends the two-digit addition children learned in second grade. A third grader lines up the ones, tens and hundreds, adds each place, and regroups when a place adds to ten or more, for example ten ones become one more ten. On this worksheet your child sees twelve plain addition problems with sums up to 999 and writes the sum.

Building Confidence regroups in one place only, On Level regroups in the ones or the tens or both, and Challenge Me regroups in both places in every problem. There are no word problems here; those have their own worksheet. Ask your child to say each regrouping aloud, such as 8 ones plus 5 ones is 13 ones, which is 1 ten and 3 ones.

What your child will learn

• Add ones, tens and hundreds in order
• Regroup ten ones as a ten and ten tens as a hundred
• Check that a sum is close to an estimate

Common Core standard: 3.NBT.A.2