Adding three-digit numbers: Fluency Drill
Grade 3 · Place Value to 10,000 · CCSS.Math.3.NBT
- 261 + 510 = ___
- 165 + 739 = ___
- 239 + 267 = ___
- 416 + 406 = ___
- 285 + 231 = ___
- 176 + 774 = ___
This is the preview. Hit "Print this worksheet" above to open a clean, ad-free, one-page version with name and date lines and writing space for each problem. A separate answer key prints on the second page for the grown-up. Tear it off before handing the practice page to your child.
Use this free Grade 3 math worksheet to help your child master Adding three-digit numbers. It belongs to our Place Value to 10,000 collection, aligns with CCSS.Math.3.NBT, and is built so a kid with a sharp pencil can finish a meaningful round of practice in roughly ten minutes.
Worksheets in this series mix straight computation, short word problems, and visual models so students see the same idea from several angles instead of only one. Mastery looks like solving most problems correctly without resorting to finger counting or repeated guessing.
Strong students can race the clock and aim for a personal best. Students who need more support can work in pairs and explain their thinking out loud, which is one of the highest-leverage moves in elementary math because it forces students to put fuzzy thinking into clear words.
Want a different angle on this skill? Try the matching variants in our Grade 3 · Place Value to 10,000 collection, or jump up to the cross-grade Place Value to 10,000 hub.
We deliberately keep the layout uncluttered: a clean header, generous spacing for kids to show their work, and a problem grid that does not feel overwhelming. Elementary students get tunnel vision on busy pages, and that visual anxiety is often mistaken for a math gap.
This worksheet is aligned to Common Core State Standard CCSS.Math.3.NBT and supports the broader Place Value to 10,000 progression that students continue to build through later grades. The same skill is revisited each year with greater abstraction, so the work your student does on this single sheet feeds into the multi-digit and multi-step problems they will see in middle school.
Pair this Adding three-digit numbers worksheet with the rest of the Grade 3 Place Value to 10,000 collection for a focused practice block that covers the standard from several angles in a single afternoon.
Sample problems on this worksheet
- 261 + 510 = ___
- 165 + 739 = ___
- 239 + 267 = ___
- 416 + 406 = ___
- 285 + 231 = ___
- 176 + 774 = ___
How to use this worksheet
Print one copy per child on standard letter or A4 paper. Set a quiet 10 to 15 minute window. Hand your student a sharpened pencil and an eraser, and let them work top to bottom. The first row is a warm-up on purpose. The last row is a stretch on purpose. Sit with them as they finish so any misconceptions surface right away instead of getting practiced into a bad habit.
If your student finishes quickly, flip the page over and ask them to write two new problems of their own that target the same skill. It's a powerful retention move. If they get stuck, pull out manipulatives that match the skill (counters for early addition, base-ten blocks for place value, fraction tiles for fractions) and work through one or two problems together before letting them try the rest on their own.
Common Core alignment
This page targets CCSS.Math.3.NBT inside the broader Place Value to 10,000 progression. The skill is introduced earlier in elementary school through concrete representations and revisited each year with greater abstraction. To see how it develops across grade levels, visit our Place Value to 10,000 hub. To see the rest of the Grade 3 work in this strand, visit the Grade 3 · Place Value to 10,000 collection.