Addition Within 20
A free printable addition within 20 worksheet with an answer key. Solve each problem. Sums go up to 20. Perfect for 1st grade addition practice at home or in class.
- Size
- US Letter (8.5 × 11 in), fits A4
- 2 pages: the worksheet and its answer key
- Level
- Grade 1
- License
- Free for personal & classroom use
About this worksheet
A free printable addition within 20 worksheet with an answer key. Solve each problem. Sums go up to 20. First graders can do it on their own once they know the strategy at the top of the page. Have your child say each fact out loud while writing the answer.
On this sheet
30 problems, starting with 8 + 3, 11 + 3, 7 + 7, 4 + 9, 15 + 2, 6 + 6, 8 + 4, 13 + 6, 13 + 5, 4 + 16, 7 + 9, 3 + 9, 2 + 15, 9 + 5, and 16 more. The answers to all of them are on page 2.
Tips for using it
- Use small objects like buttons or cereal to check tricky problems.
- Teach the make-10 trick early: 8 + 5 is the same as 8 + 2 + 3 = 13.
- Doubles (6 + 6, 7 + 7) are easy to remember and help with near doubles like 6 + 7.
- For column addition, always start with the ones column on the right.
Printing tips
Download the PDF and print at 100% (or “fit to page” on A4). Page 1 is the worksheet and page 2 is the answer key with the answers in red; print just page 1 if you want to keep the answers for checking. The PNG shows page 1 only. Free for personal, family and classroom use.
