Addition Within 100: Games, Strategies & Worksheet
Adding within 100 means two-digit sums like 46 + 37. Children combine tens and ones, and regroup when the ones make more than 9.
➕ Play the addition within 100 game 🖨️ Printable worksheet
Tricks that make it easier
- Add the tens, then the ones: 46 + 37 = 70 + 13 = 83.
- Round and adjust: 46 + 29 = 46 + 30 − 1 = 75.
- Count on in tens from the bigger number: 58 + 30 → 68, 78, 88.
Try these
- 19 + 21 =
Answer
40 - 18 + 14 =
Answer
32 - 65 + 13 =
Answer
78 - 42 + 31 =
Answer
73 - 46 + 10 =
Answer
56 - 20 + 53 =
Answer
73
Common mistakes
- Forgetting to regroup when the ones add up to more than 9.
- Adding tens to ones (for example 40 + 7 = 11).
- Lining up digits incorrectly in written methods.
A five-day practice plan
| Day | What to do (10 minutes) |
|---|---|
| Day 1 | Play Addition Adventure on this skill for 5–10 minutes. Read the explanation after every mistake. |
| Day 2 | Learn one trick from this page and use it out loud while you play. |
| Day 3 | Print the worksheet and try it without help. Mark it with the answer key together. |
| Day 4 | Play again and try to beat your personal best score or get three stars. |
| Day 5 | Mix it up: try the ⏱️ Timed test, or ask your child to explain the skill to you in their own words. |
Suits 2nd Grade and 3rd Grade.
Frequently asked questions
What does addition within 100 mean?
It means adding numbers where the total is 100 or less.
How can I help my child get faster at addition?
Practice a few minutes every day with games and number bonds, and encourage strategies like counting on from the bigger number and bridging through 10 instead of counting from one.
Is there a printable version?
Yes. The free addition within 100 worksheet has 30 questions and an answer key, and you can make a new set in one click.