Addition Within 20 Worksheet Generator
Sums stay within 20, with missing-addend items added at the challenge level. Encourage counting on from the larger number instead of restarting at one.
Print at 100% for exact sizing. Choose “Save as PDF” in the print dialog for a digital copy. Free sheets include 3 prints per day; everything on the sheet is generated in your browser.
What this sheet practices
Sums stay within 20, with missing-addend items added at the challenge level. Encourage counting on from the larger number instead of restarting at one.
Errors worth watching for
- Forgetting to count the starting number when counting on.
- Adding the digits but losing track of ten (8 + 6 = 15).
How to use it
- Set the difficulty. Easy narrows the range; challenge adds missing values or extra steps.
- Choose how many questions and how many fit on a page. Ten per page is the most readable default.
- Print, or save as PDF. Replace any single question with the circular arrow if it does not fit your group.
At a glance
About this generator
Should my child use fingers?
Yes at first. Fingers are a valid model; the goal is to move to known facts by the end of the year.
What does the challenge level add?
Missing addends such as 7 + ___ = 13, which require the inverse operation.
Can I print this worksheet on A4 paper?
Yes. Switch Paper to A4 in the settings panel. The layout recalculates the page height and keeps 0.5-inch margins, so nothing is cut off.
Is an answer key included?
The generator always produces an answer key and worked solutions. They are part of the pass; the student sheet can be previewed and printed for free.